Bump version numbers for 1.2.19 release.

Update translations.
Merge branch '1866-blog-controller' into 'master'
2026-02-12 02:39:05 +01:00 · 2021-03-25 17:36:04 +00:00 · 2021-03-25 17:34:02 +00:00 · 2021-03-25 17:25:43 +00:00 · 2021-03-25 15:47:18 +00:00 · 2021-03-25 13:29:43 +00:00
2086 changed files with 117599 additions and 52808 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -20,7 +20,9 @@ local.properties
 .idea/*
 !.idea/runConfigurations/
 !.idea/codeStyleSettings.xml
+!.idea/codeStyles
 .gradle
 build/
+captures
 *.iml
 projectFilesBackup/
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,20 +1,87 @@
-image: registry.gitlab.com/fdroid/ci-images-base:latest
+image: briar/ci-image-android:latest

-cache:
-  paths:
-    - .gradle/wrapper
-    - .gradle/caches
+stages:
+  - test
+  - optional_tests
+  - check_reproducibility

-before_script:
-  - export GRADLE_USER_HOME=$PWD/.gradle
-#  - export ANDROID_COMPILE_SDK=`sed -n 's,.*compileSdkVersion\s*\([0-9][0-9]*\).*,\1,p' app/build.gradle`
-#  - echo y | android --silent update sdk --no-ui --filter android-${ANDROID_COMPILE_SDK}
-
-test:
-  script:
-    - ./gradlew test
-
-after_script:
-    # this file changes every time but should not be cached
+.base-test:
+  before_script:
+    - set -e
+    - export GRADLE_USER_HOME=$PWD/.gradle
+  cache:
+    key: "$CI_COMMIT_REF_SLUG"
+    paths:
+      - .gradle/wrapper
+      - .gradle/caches
+  after_script:
+    # these file change every time and should not be cached
    - rm -f $GRADLE_USER_HOME/caches/modules-2/modules-2.lock
    - rm -fr $GRADLE_USER_HOME/caches/*/plugin-resolution/
+
+test:
+  extends: .base-test
+  stage: test
+  script:
+    - ./gradlew --no-daemon -Djava.security.egd=file:/dev/urandom animalSnifferMain animalSnifferTest
+    - ./gradlew --no-daemon -Djava.security.egd=file:/dev/urandom check
+
+android test:
+  extends: .base-test
+  stage: optional_tests
+  image: briar/ci-image-android-emulator:latest
+  script:
+    # start emulator first, so it can fail early
+    - start-emulator.sh
+    # run normal and screenshot tests together (exclude Large tests)
+    - ./gradlew -Djava.security.egd=file:/dev/urandom connectedAndroidTest -Pandroid.testInstrumentationRunnerArguments.notAnnotation=androidx.test.filters.LargeTest
+  artifacts:
+    name: "${CI_PROJECT_PATH}_${CI_JOB_STAGE}_${CI_COMMIT_REF_NAME}_${CI_COMMIT_SHA}"
+    paths:
+      - kernel.log
+      - logcat.txt
+    expire_in: 3 days
+    when: on_failure
+  when: manual
+  except:
+    - tags
+  tags:
+    - kvm
+
+test_reproducible:
+  stage: check_reproducibility
+  script:
+    - "curl -X POST -F token=${RELEASE_CHECK_TOKEN} -F ref=master -F variables[RELEASE_TAG]=${CI_COMMIT_REF_NAME} https://code.briarproject.org/api/v4/projects/61/trigger/pipeline"
+  only:
+    - tags
+
+.optional_tests:
+  stage: optional_tests
+  before_script:
+    - set -e
+    - export GRADLE_USER_HOME=$PWD/.gradle
+
+  cache:
+    key: "$CI_COMMIT_REF_SLUG"
+    paths:
+      - .gradle/wrapper
+      - .gradle/caches
+
+  script:
+    - OPTIONAL_TESTS=org.briarproject.bramble.plugin.tor.BridgeTest ./gradlew --info bramble-java:test --tests BridgeTest
+
+  after_script:
+    # these file change every time but should not be cached
+    - rm -f $GRADLE_USER_HOME/caches/modules-2/modules-2.lock
+    - rm -fr $GRADLE_USER_HOME/caches/*/plugin-resolution/
+
+manual_tests:
+  extends: .optional_tests
+  when: manual
+  except:
+    - tags
+
+pre_release_tests:
+  extends: .optional_tests
+  only:
+    - tags
--- a/.idea/codeStyles/Project.xml
+++ b/.idea/codeStyles/Project.xml
@@ -0,0 +1,205 @@
+<component name="ProjectCodeStyleConfiguration">
+  <code_scheme name="Project" version="173">
+    <JavaCodeStyleSettings>
+      <option name="ANNOTATION_PARAMETER_WRAP" value="1" />
+      <option name="IMPORT_LAYOUT_TABLE">
+        <value>
+          <package name="android" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="com" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="junit" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="net" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="org" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="java" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="javax" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="" withSubpackages="true" static="true" />
+          <emptyLine />
+        </value>
+      </option>
+      <option name="JD_ALIGN_PARAM_COMMENTS" value="false" />
+      <option name="JD_ALIGN_EXCEPTION_COMMENTS" value="false" />
+    </JavaCodeStyleSettings>
+    <JetCodeStyleSettings>
+      <option name="PACKAGES_TO_USE_STAR_IMPORTS">
+        <value />
+      </option>
+      <option name="PACKAGES_IMPORT_LAYOUT">
+        <value>
+          <package name="" alias="false" withSubpackages="true" />
+          <package name="java" alias="false" withSubpackages="true" />
+          <package name="javax" alias="false" withSubpackages="true" />
+          <package name="kotlin" alias="false" withSubpackages="true" />
+          <package name="" alias="true" withSubpackages="true" />
+        </value>
+      </option>
+      <option name="NAME_COUNT_TO_USE_STAR_IMPORT" value="2147483647" />
+      <option name="NAME_COUNT_TO_USE_STAR_IMPORT_FOR_MEMBERS" value="2147483647" />
+      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
+    </JetCodeStyleSettings>
+    <XML>
+      <option name="XML_LEGACY_SETTINGS_IMPORTED" value="true" />
+    </XML>
+    <codeStyleSettings language="Groovy">
+      <indentOptions>
+        <option name="USE_TAB_CHARACTER" value="true" />
+        <option name="SMART_TABS" value="true" />
+      </indentOptions>
+    </codeStyleSettings>
+    <codeStyleSettings language="JAVA">
+      <option name="RIGHT_MARGIN" value="80" />
+      <option name="ALIGN_MULTILINE_PARAMETERS" value="false" />
+      <option name="ALIGN_MULTILINE_RESOURCES" value="false" />
+      <option name="ALIGN_MULTILINE_FOR" value="false" />
+      <option name="SPACE_BEFORE_ARRAY_INITIALIZER_LBRACE" value="true" />
+      <option name="CALL_PARAMETERS_WRAP" value="1" />
+      <option name="METHOD_PARAMETERS_WRAP" value="1" />
+      <option name="RESOURCE_LIST_WRAP" value="1" />
+      <option name="EXTENDS_LIST_WRAP" value="1" />
+      <option name="THROWS_LIST_WRAP" value="1" />
+      <option name="EXTENDS_KEYWORD_WRAP" value="1" />
+      <option name="THROWS_KEYWORD_WRAP" value="1" />
+      <option name="METHOD_CALL_CHAIN_WRAP" value="1" />
+      <option name="BINARY_OPERATION_WRAP" value="1" />
+      <option name="TERNARY_OPERATION_WRAP" value="1" />
+      <option name="FOR_STATEMENT_WRAP" value="1" />
+      <option name="ARRAY_INITIALIZER_WRAP" value="1" />
+      <option name="ASSIGNMENT_WRAP" value="1" />
+      <option name="ASSERT_STATEMENT_WRAP" value="1" />
+      <option name="PARAMETER_ANNOTATION_WRAP" value="1" />
+      <option name="VARIABLE_ANNOTATION_WRAP" value="1" />
+      <option name="ENUM_CONSTANTS_WRAP" value="1" />
+      <indentOptions>
+        <option name="USE_TAB_CHARACTER" value="true" />
+        <option name="SMART_TABS" value="true" />
+      </indentOptions>
+    </codeStyleSettings>
+    <codeStyleSettings language="XML">
+      <indentOptions>
+        <option name="CONTINUATION_INDENT_SIZE" value="4" />
+        <option name="USE_TAB_CHARACTER" value="true" />
+        <option name="SMART_TABS" value="true" />
+      </indentOptions>
+      <arrangement>
+        <rules>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>xmlns:android</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>xmlns:.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>BY_NAME</order>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*:id</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*:name</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>name</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>style</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>BY_NAME</order>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>ANDROID_ATTRIBUTE_ORDER</order>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>.*</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>BY_NAME</order>
+            </rule>
+          </section>
+        </rules>
+      </arrangement>
+    </codeStyleSettings>
+    <codeStyleSettings language="kotlin">
+      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
+      <option name="PARAMETER_ANNOTATION_WRAP" value="1" />
+      <option name="VARIABLE_ANNOTATION_WRAP" value="1" />
+      <option name="ENUM_CONSTANTS_WRAP" value="1" />
+    </codeStyleSettings>
+  </code_scheme>
+</component>
--- a/.idea/codeStyles/codeStyleConfig.xml
+++ b/.idea/codeStyles/codeStyleConfig.xml
@@ -0,0 +1,5 @@
+<component name="ProjectCodeStyleConfiguration">
+  <state>
+    <option name="USE_PER_PROJECT_SETTINGS" value="true" />
+  </state>
+</component>
--- a/.idea/dictionaries/briar.xml
+++ b/.idea/dictionaries/briar.xml
@@ -0,0 +1,14 @@
+<component name="ProjectDictionaryState">
+  <dictionary name="briar">
+    <words>
+      <w>briar</w>
+      <w>briarproject</w>
+      <w>emoji</w>
+      <w>encrypter</w>
+      <w>identicon</w>
+      <w>introducee</w>
+      <w>introducer</w>
+      <w>onboarding</w>
+    </words>
+  </dictionary>
+</component>
--- a/.idea/runConfigurations/All_tests.xml
+++ b/.idea/runConfigurations/All_tests.xml
@@ -1,28 +1,21 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
-    <module name="briar-android" />
-    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
-    <option name="ALTERNATIVE_JRE_PATH" />
+    <module name="briar.briar-android" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
-    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
-    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-android" />
-    <option name="ENV_VARIABLES" />
-    <option name="PASS_PARENT_ENVS" value="true" />
-    <option name="TEST_SEARCH_SCOPE">
-      <value defaultName="singleModule" />
-    </option>
-    <envs />
-    <patterns />
-    <method>
+    <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$/briar-android" />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-api" run_configuration_type="AndroidJUnit" />
      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-core" run_configuration_type="AndroidJUnit" />
-      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-j2se" run_configuration_type="AndroidJUnit" />
+      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-android" run_configuration_type="AndroidJUnit" />
+      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-java" run_configuration_type="AndroidJUnit" />
+      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in briar-api" run_configuration_type="AndroidJUnit" />
      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in briar-core" run_configuration_type="AndroidJUnit" />
+      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in briar-headless" run_configuration_type="AndroidJUnit" />
    </method>
  </configuration>
 </component>
--- a/.idea/runConfigurations/All_tests_in_bramble_android.xml
+++ b/.idea/runConfigurations/All_tests_in_bramble_android.xml
@@ -0,0 +1,14 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="All tests in bramble-android" type="AndroidJUnit" factoryName="Android JUnit">
+    <module name="briar.bramble-android" />
+    <option name="PACKAGE_NAME" value="" />
+    <option name="MAIN_CLASS_NAME" value="" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="package" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-android" />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/All_tests_in_bramble_api.xml
+++ b/.idea/runConfigurations/All_tests_in_bramble_api.xml
@@ -1,23 +1,14 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in bramble-api" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
-    <module name="bramble-api" />
-    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
-    <option name="ALTERNATIVE_JRE_PATH" />
+    <module name="briar.bramble-api" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
-    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-api" />
-    <option name="ENV_VARIABLES" />
-    <option name="PASS_PARENT_ENVS" value="true" />
-    <option name="TEST_SEARCH_SCOPE">
-      <value defaultName="singleModule" />
-    </option>
-    <envs />
-    <patterns />
-    <method />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
  </configuration>
 </component>
--- a/.idea/runConfigurations/All_tests_in_bramble_core.xml
+++ b/.idea/runConfigurations/All_tests_in_bramble_core.xml
@@ -1,23 +1,14 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in bramble-core" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
-    <module name="bramble-core" />
-    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
-    <option name="ALTERNATIVE_JRE_PATH" />
+    <module name="briar.bramble-core" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
-    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-core" />
-    <option name="ENV_VARIABLES" />
-    <option name="PASS_PARENT_ENVS" value="true" />
-    <option name="TEST_SEARCH_SCOPE">
-      <value defaultName="singleModule" />
-    </option>
-    <envs />
-    <patterns />
-    <method />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
  </configuration>
 </component>
--- a/.idea/runConfigurations/All_tests_in_bramble_j2se.xml
+++ b/.idea/runConfigurations/All_tests_in_bramble_j2se.xml
@@ -1,23 +0,0 @@
-<component name="ProjectRunConfigurationManager">
-  <configuration default="false" name="All tests in bramble-j2se" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
-    <module name="bramble-j2se" />
-    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
-    <option name="ALTERNATIVE_JRE_PATH" />
-    <option name="PACKAGE_NAME" value="" />
-    <option name="MAIN_CLASS_NAME" value="" />
-    <option name="METHOD_NAME" value="" />
-    <option name="TEST_OBJECT" value="package" />
-    <option name="VM_PARAMETERS" value="-ea -Djava.library.path=libs" />
-    <option name="PARAMETERS" value="" />
-    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-j2se" />
-    <option name="ENV_VARIABLES" />
-    <option name="PASS_PARENT_ENVS" value="true" />
-    <option name="TEST_SEARCH_SCOPE">
-      <value defaultName="singleModule" />
-    </option>
-    <envs />
-    <patterns />
-    <method />
-  </configuration>
-</component>
--- a/.idea/runConfigurations/All_tests_in_bramble_java.xml
+++ b/.idea/runConfigurations/All_tests_in_bramble_java.xml
@@ -0,0 +1,15 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="All tests in bramble-java" type="AndroidJUnit" factoryName="Android JUnit">
+    <module name="briar.bramble-java" />
+    <option name="PACKAGE_NAME" value="" />
+    <option name="MAIN_CLASS_NAME" value="" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="package" />
+    <option name="VM_PARAMETERS" value="-ea -Djava.library.path=libs" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-java" />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/All_tests_in_briar_android.xml
+++ b/.idea/runConfigurations/All_tests_in_briar_android.xml
@@ -1,23 +1,14 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in briar-android" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
-    <module name="briar-android" />
-    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
-    <option name="ALTERNATIVE_JRE_PATH" />
+    <module name="briar.briar-android" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
-    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-android" />
-    <option name="ENV_VARIABLES" />
-    <option name="PASS_PARENT_ENVS" value="true" />
-    <option name="TEST_SEARCH_SCOPE">
-      <value defaultName="singleModule" />
-    </option>
-    <envs />
-    <patterns />
-    <method />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
  </configuration>
 </component>
--- a/.idea/runConfigurations/All_tests_in_briar_api.xml
+++ b/.idea/runConfigurations/All_tests_in_briar_api.xml
@@ -0,0 +1,14 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="All tests in briar-api" type="AndroidJUnit" factoryName="Android JUnit">
+    <module name="briar.briar-api" />
+    <option name="PACKAGE_NAME" value="" />
+    <option name="MAIN_CLASS_NAME" value="" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="package" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-api" />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/All_tests_in_briar_core.xml
+++ b/.idea/runConfigurations/All_tests_in_briar_core.xml
@@ -1,23 +1,14 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in briar-core" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
-    <module name="briar-core" />
-    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
-    <option name="ALTERNATIVE_JRE_PATH" />
+    <module name="briar.briar-core" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
-    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-core" />
-    <option name="ENV_VARIABLES" />
-    <option name="PASS_PARENT_ENVS" value="true" />
-    <option name="TEST_SEARCH_SCOPE">
-      <value defaultName="singleModule" />
-    </option>
-    <envs />
-    <patterns />
-    <method />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
  </configuration>
 </component>
--- a/.idea/runConfigurations/All_tests_in_briar_headless.xml
+++ b/.idea/runConfigurations/All_tests_in_briar_headless.xml
@@ -0,0 +1,15 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="All tests in briar-headless" type="AndroidJUnit" factoryName="Android JUnit">
+    <module name="briar.briar-headless" />
+    <option name="PACKAGE_NAME" value="org.briarproject.briar.headless" />
+    <option name="MAIN_CLASS_NAME" value="" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="package" />
+    <option name="VM_PARAMETERS" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$/briar-headless" />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/BridgeTest.xml
+++ b/.idea/runConfigurations/BridgeTest.xml
@@ -0,0 +1,24 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="BridgeTest" type="AndroidJUnit" factoryName="Android JUnit" nameIsGenerated="true">
+    <module name="briar.bramble-java" />
+    <useClassPathOnly />
+    <extension name="coverage">
+      <pattern>
+        <option name="PATTERN" value="org.briarproject.bramble.plugin.tor.*" />
+        <option name="ENABLED" value="true" />
+      </pattern>
+    </extension>
+    <option name="PACKAGE_NAME" value="org.briarproject.bramble.plugin.tor" />
+    <option name="MAIN_CLASS_NAME" value="org.briarproject.bramble.plugin.tor.BridgeTest" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="class" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="$MODULE_DIR$" />
+    <envs>
+      <env name="OPTIONAL_TESTS" value="org.briarproject.bramble.plugin.tor.BridgeTest" />
+    </envs>
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/H2_Performance_Test.xml
+++ b/.idea/runConfigurations/H2_Performance_Test.xml
@@ -0,0 +1,14 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="H2 Performance Test" type="AndroidJUnit" factoryName="Android JUnit">
+    <module name="briar.bramble-core" />
+    <option name="PACKAGE_NAME" value="org.briarproject.bramble.db" />
+    <option name="MAIN_CLASS_NAME" value="org.briarproject.bramble.db.H2DatabasePerformanceTest" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="class" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="" />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/HyperSQL_Performance_Test.xml
+++ b/.idea/runConfigurations/HyperSQL_Performance_Test.xml
@@ -0,0 +1,14 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="HyperSQL Performance Test" type="AndroidJUnit" factoryName="Android JUnit">
+    <module name="briar.bramble-core" />
+    <option name="PACKAGE_NAME" value="org.briarproject.bramble.db" />
+    <option name="MAIN_CLASS_NAME" value="org.briarproject.bramble.db.HyperSqlDatabasePerformanceTest" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="class" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="" />
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/Instrumentation_Tests__destroys_DB_.xml
+++ b/.idea/runConfigurations/Instrumentation_Tests__destroys_DB_.xml
@@ -0,0 +1,51 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="Instrumentation Tests (destroys DB)" type="AndroidTestRunConfigurationType" factoryName="Android Instrumented Tests">
+    <module name="briar.briar-android" />
+    <option name="TESTING_TYPE" value="1" />
+    <option name="METHOD_NAME" value="" />
+    <option name="CLASS_NAME" value="" />
+    <option name="PACKAGE_NAME" value="org.briarproject.briar.android" />
+    <option name="INSTRUMENTATION_RUNNER_CLASS" value="" />
+    <option name="EXTRA_OPTIONS" value="-e notAnnotation androidx.test.filters.LargeTest" />
+    <option name="INCLUDE_GRADLE_EXTRA_OPTIONS" value="true" />
+    <option name="CLEAR_LOGCAT" value="false" />
+    <option name="SHOW_LOGCAT_AUTOMATICALLY" value="false" />
+    <option name="SKIP_NOOP_APK_INSTALLATIONS" value="true" />
+    <option name="FORCE_STOP_RUNNING_APP" value="true" />
+    <option name="TARGET_SELECTION_MODE" value="DEVICE_AND_SNAPSHOT_COMBO_BOX" />
+    <option name="DEBUGGER_TYPE" value="Auto" />
+    <Auto>
+      <option name="USE_JAVA_AWARE_DEBUGGER" value="false" />
+      <option name="SHOW_STATIC_VARS" value="true" />
+      <option name="WORKING_DIR" value="" />
+      <option name="TARGET_LOGGING_CHANNELS" value="lldb process:gdb-remote packets" />
+      <option name="SHOW_OPTIMIZED_WARNING" value="true" />
+    </Auto>
+    <Hybrid>
+      <option name="USE_JAVA_AWARE_DEBUGGER" value="false" />
+      <option name="SHOW_STATIC_VARS" value="true" />
+      <option name="WORKING_DIR" value="" />
+      <option name="TARGET_LOGGING_CHANNELS" value="lldb process:gdb-remote packets" />
+      <option name="SHOW_OPTIMIZED_WARNING" value="true" />
+    </Hybrid>
+    <Java />
+    <Native>
+      <option name="USE_JAVA_AWARE_DEBUGGER" value="false" />
+      <option name="SHOW_STATIC_VARS" value="true" />
+      <option name="WORKING_DIR" value="" />
+      <option name="TARGET_LOGGING_CHANNELS" value="lldb process:gdb-remote packets" />
+      <option name="SHOW_OPTIMIZED_WARNING" value="true" />
+    </Native>
+    <Profilers>
+      <option name="ADVANCED_PROFILING_ENABLED" value="false" />
+      <option name="STARTUP_PROFILING_ENABLED" value="false" />
+      <option name="STARTUP_CPU_PROFILING_ENABLED" value="false" />
+      <option name="STARTUP_CPU_PROFILING_CONFIGURATION_NAME" value="Sample Java Methods" />
+      <option name="STARTUP_NATIVE_MEMORY_PROFILING_ENABLED" value="false" />
+      <option name="NATIVE_MEMORY_SAMPLE_RATE_BYTES" value="2048" />
+    </Profilers>
+    <method v="2">
+      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
+    </method>
+  </configuration>
+</component>
--- a/.idea/runConfigurations/briar_headless.xml
+++ b/.idea/runConfigurations/briar_headless.xml
@@ -0,0 +1,16 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="briar-headless" type="JetRunConfigurationType" singleton="true">
+    <module name="briar.briar-headless" />
+    <option name="VM_PARAMETERS" value="" />
+    <option name="PROGRAM_PARAMETERS" value="-v" />
+    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
+    <option name="ALTERNATIVE_JRE_PATH" />
+    <option name="PASS_PARENT_ENVS" value="true" />
+    <option name="MAIN_CLASS_NAME" value="org.briarproject.briar.headless.MainKt" />
+    <option name="WORKING_DIRECTORY" value="" />
+    <method v="2">
+      <option name="Make" enabled="true" />
+      <option name="Gradle.BeforeRunTask" enabled="true" tasks="jar" externalProjectPath="$PROJECT_DIR$/briar-headless" vmOptions="" scriptParameters="" />
+    </method>
+  </configuration>
+</component>
--- a/TRANSLATION.md
+++ b/TRANSLATION.md
@@ -0,0 +1,9 @@
+Translations for this project are managed through Transifex:
+
+https://transifex.com/otf/briar
+
+If you'd like to volunteer as a translator, please create a Transifex account and request to be
+added to the project's translation team. The Localization Lab has some instructions and advice for
+translators here:
+
+https://wiki.localizationlab.org/index.php/Briar
--- a/bramble-android/.gitignore
+++ b/bramble-android/.gitignore
@@ -3,3 +3,4 @@ gen
 build
 .settings
 src/main/res/raw/*.zip
+src/main/jniLibs
--- a/bramble-android/build.gradle
+++ b/bramble-android/build.gradle
@@ -1,104 +1,115 @@
-import de.undercouch.gradle.tasks.download.Download
-import de.undercouch.gradle.tasks.download.Verify
+import com.android.build.gradle.tasks.MergeResources

 apply plugin: 'com.android.library'
 apply plugin: 'witness'
-apply plugin: 'de.undercouch.download'
+apply from: 'witness.gradle'

 android {
-	compileSdkVersion 23
-	buildToolsVersion "23.0.3"
+	compileSdkVersion 30
+	buildToolsVersion '30.0.2'
+
+	packagingOptions {
+		doNotStrip '**/*.so'
+	}

 	defaultConfig {
-		minSdkVersion 14
-		targetSdkVersion 22
-		versionCode 14
-		versionName "0.14"
+		minSdkVersion 16
+		targetSdkVersion 29
+		versionCode 10219
+		versionName "1.2.19"
 		consumerProguardFiles 'proguard-rules.txt'
+
+		testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
 	}

 	compileOptions {
-		sourceCompatibility JavaVersion.VERSION_1_7
-		targetCompatibility JavaVersion.VERSION_1_7
+		sourceCompatibility JavaVersion.VERSION_1_8
+		targetCompatibility JavaVersion.VERSION_1_8
 	}
+
+	lintOptions {
+		// FIXME
+		warning "LintError"
+		warning "InvalidPackage"
+		warning "MissingPermission"
+		warning "InlinedApi", "ObsoleteSdkInt", "Override", "NewApi", "UnusedAttribute"
+	}
+}
+
+configurations {
+	tor
 }

 dependencies {
-	compile project(':bramble-core')
-	compile fileTree(dir: 'libs', include: '*.jar')
-	provided 'javax.annotation:jsr250-api:1.0'
+	implementation project(path: ':bramble-core', configuration: 'default')
+	tor 'org.briarproject:tor-android:0.3.5.13@zip'
+	tor 'org.briarproject:obfs4proxy-android:0.0.12-dev-40245c4a@zip'
+
+	annotationProcessor 'com.google.dagger:dagger-compiler:2.24'
+
+	compileOnly 'javax.annotation:jsr250-api:1.0'
+
+	testImplementation project(path: ':bramble-api', configuration: 'testOutput')
+	testImplementation 'junit:junit:4.12'
+	testImplementation "org.jmock:jmock:2.8.2"
+	testImplementation "org.jmock:jmock-junit4:2.8.2"
+	testImplementation "org.jmock:jmock-legacy:2.8.2"
 }

-def torBinaryDir = 'src/main/res/raw'
+def torBinariesDir = 'src/main/res/raw'
+def torLibsDir = 'src/main/jniLibs'

-task downloadTorGeoIp(type: Download) {
-	src 'https://briarproject.org/build/geoip-2017-05-02.zip'
-	dest "$torBinaryDir/geoip.zip"
-	onlyIfNewer true
-}
-
-task downloadTorBinaryArm(type: Download) {
-	src 'https://briarproject.org/build/tor-0.2.9.11-arm.zip'
-	dest "$torBinaryDir/tor_arm.zip"
-	onlyIfNewer true
-}
-
-task downloadTorBinaryArmPie(type: Download) {
-	src 'https://briarproject.org/build/tor-0.2.9.11-arm-pie.zip'
-	dest "$torBinaryDir/tor_arm_pie.zip"
-	onlyIfNewer true
-}
-
-task downloadTorBinaryX86(type: Download) {
-	src 'https://briarproject.org/build/tor-0.2.9.11-x86.zip'
-	dest "$torBinaryDir/tor_x86.zip"
-	onlyIfNewer true
-}
-
-task downloadTorBinaryX86Pie(type: Download) {
-	src 'https://briarproject.org/build/tor-0.2.9.11-x86-pie.zip'
-	dest "$torBinaryDir/tor_x86_pie.zip"
-	onlyIfNewer true
-}
-
-task verifyTorGeoIp(type: Verify, dependsOn: 'downloadTorGeoIp') {
-	src "$torBinaryDir/geoip.zip"
-	algorithm 'SHA-256'
-	checksum '51f4d1272fb867e1f3b36b67a584e2a33c40b40f62305457d799fd399cd77c9b'
-}
-
-task verifyTorBinaryArm(type: Verify, dependsOn: 'downloadTorBinaryArm') {
-	src "$torBinaryDir/tor_arm.zip"
-	algorithm 'SHA-256'
-	checksum '1da6008663a8ad98b349e62acbbf42c379f65ec504fa467cb119c187cd5a4c6b'
-}
-
-task verifyTorBinaryArmPie(type: Verify, dependsOn: 'downloadTorBinaryArmPie') {
-	src "$torBinaryDir/tor_arm_pie.zip"
-	algorithm 'SHA-256'
-	checksum 'eb061f880829e05f104690ac744848133f2dacef04759d425a2cff0df32c271e'
-}
-
-task verifyTorBinaryX86(type: Verify, dependsOn: 'downloadTorBinaryX86') {
-	src "$torBinaryDir/tor_x86.zip"
-	algorithm 'SHA-256'
-	checksum 'f5308aff8303daca082f82227d02b51ddedba4ab1d1420739ada0427ae5dbb41'
-}
-
-task verifyTorBinaryX86Pie(type: Verify, dependsOn: 'downloadTorBinaryX86Pie') {
-	src "$torBinaryDir/tor_x86_pie.zip"
-	algorithm 'SHA-256'
-	checksum '889a6c81ac73d05d35ed610ca5a913cee44d333e4ae1749c2a107f2f7dd8197b'
-}
-
-project.afterEvaluate {
-	preBuild.dependsOn {
-		[
-				'verifyTorGeoIp',
-				'verifyTorBinaryArm',
-				'verifyTorBinaryArmPie',
-				'verifyTorBinaryX86',
-				'verifyTorBinaryX86Pie'
-		]
+task cleanTorBinaries {
+	doLast {
+		delete fileTree(torBinariesDir) { include '*.zip' }
+		delete fileTree(torLibsDir) { include '**/*.so' }
 	}
 }
+
+clean.dependsOn cleanTorBinaries
+
+task unpackTorBinaries {
+	doLast {
+		copy {
+			from configurations.tor.collect { zipTree(it) }
+			into torBinariesDir
+			include 'geoip.zip'
+		}
+		configurations.tor.each { outer ->
+			zipTree(outer).each { inner ->
+				if (inner.name.endsWith('_arm_pie.zip')) {
+					copy {
+						from zipTree(inner)
+						into torLibsDir
+						rename '(.*)', 'armeabi-v7a/lib$1.so'
+					}
+				} else if (inner.name.endsWith('_arm64_pie.zip')) {
+					copy {
+						from zipTree(inner)
+						into torLibsDir
+						rename '(.*)', 'arm64-v8a/lib$1.so'
+					}
+				} else if (inner.name.endsWith('_x86_pie.zip')) {
+					copy {
+						from zipTree(inner)
+						into torLibsDir
+						rename '(.*)', 'x86/lib$1.so'
+					}
+				} else if (inner.name.endsWith('_x86_64_pie.zip')) {
+					copy {
+						from zipTree(inner)
+						into torLibsDir
+						rename '(.*)', 'x86_64/lib$1.so'
+					}
+				}
+			}
+		}
+	}
+	dependsOn cleanTorBinaries
+}
+
+tasks.withType(MergeResources) {
+	inputs.dir torBinariesDir
+	inputs.dir torLibsDir
+	dependsOn unpackTorBinaries
+}
--- a/bramble-android/libs/jtorctl-briar.jar
+++ b/bramble-android/libs/jtorctl-briar.jar
--- a/bramble-android/proguard-rules.txt
+++ b/bramble-android/proguard-rules.txt
@@ -8,6 +8,10 @@
 -dontwarn dagger.**
 -dontnote dagger.**

+-keep class net.i2p.crypto.eddsa.** { *; }
+
+-keep class org.whispersystems.curve25519.** { *; }
+
 -dontwarn sun.misc.Unsafe
 -dontnote com.google.common.**

--- a/bramble-android/src/main/AndroidManifest.xml
+++ b/bramble-android/src/main/AndroidManifest.xml
@@ -2,23 +2,22 @@
 	package="org.briarproject.bramble"
 	xmlns:android="http://schemas.android.com/apk/res/android">

-	<uses-feature android:name="android.hardware.bluetooth"/>
+	<uses-feature android:name="android.hardware.bluetooth" android:required="false"/>

 	<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
 	<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
 	<uses-permission android:name="android.permission.BLUETOOTH"/>
 	<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
 	<uses-permission android:name="android.permission.INTERNET"/>
-	<uses-permission android:name="android.permission.READ_LOGS"/>
 	<uses-permission android:name="android.permission.WAKE_LOCK"/>
-	<!-- Since API 23, this is needed to add contacts via Bluetooth -->
-	<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

 	<application
 		android:allowBackup="false"
 		android:label="@string/app_name"
 		android:supportsRtl="true">

+		<receiver android:name=".system.AlarmReceiver" />
+
 	</application>

 </manifest>
--- a/bramble-android/src/main/java/org/briarproject/bramble/BrambleAndroidEagerSingletons.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/BrambleAndroidEagerSingletons.java
@@ -0,0 +1,24 @@
+package org.briarproject.bramble;
+
+import org.briarproject.bramble.battery.AndroidBatteryModule;
+import org.briarproject.bramble.network.AndroidNetworkModule;
+import org.briarproject.bramble.reporting.ReportingModule;
+
+public interface BrambleAndroidEagerSingletons {
+
+	void inject(AndroidBatteryModule.EagerSingletons init);
+
+	void inject(AndroidNetworkModule.EagerSingletons init);
+
+	void inject(ReportingModule.EagerSingletons init);
+
+	class Helper {
+
+		public static void injectEagerSingletons(
+				BrambleAndroidEagerSingletons c) {
+			c.inject(new AndroidBatteryModule.EagerSingletons());
+			c.inject(new AndroidNetworkModule.EagerSingletons());
+			c.inject(new ReportingModule.EagerSingletons());
+		}
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/BrambleAndroidModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/BrambleAndroidModule.java
@@ -1,13 +1,25 @@
 package org.briarproject.bramble;

-import org.briarproject.bramble.plugin.AndroidPluginModule;
+import org.briarproject.bramble.battery.AndroidBatteryModule;
+import org.briarproject.bramble.network.AndroidNetworkModule;
+import org.briarproject.bramble.plugin.tor.CircumventionModule;
+import org.briarproject.bramble.reporting.ReportingModule;
+import org.briarproject.bramble.socks.SocksModule;
 import org.briarproject.bramble.system.AndroidSystemModule;
+import org.briarproject.bramble.system.AndroidTaskSchedulerModule;
+import org.briarproject.bramble.system.AndroidWakefulIoExecutorModule;

 import dagger.Module;

@Module(includes = {
-		AndroidPluginModule.class,
-		AndroidSystemModule.class
+		AndroidBatteryModule.class,
+		AndroidNetworkModule.class,
+		AndroidSystemModule.class,
+		AndroidTaskSchedulerModule.class,
+		AndroidWakefulIoExecutorModule.class,
+		CircumventionModule.class,
+		ReportingModule.class,
+		SocksModule.class
 })
 public class BrambleAndroidModule {
 }
--- a/bramble-android/src/main/java/org/briarproject/bramble/BrambleAppComponent.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/BrambleAppComponent.java
@@ -0,0 +1,8 @@
+package org.briarproject.bramble;
+
+import org.briarproject.bramble.api.system.AlarmListener;
+
+public interface BrambleAppComponent {
+
+	AlarmListener alarmListener();
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/BrambleApplication.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/BrambleApplication.java
@@ -0,0 +1,6 @@
+package org.briarproject.bramble;
+
+public interface BrambleApplication {
+
+	BrambleAppComponent getBrambleAppComponent();
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/account/AndroidAccountManager.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/account/AndroidAccountManager.java
@@ -0,0 +1,137 @@
+package org.briarproject.bramble.account;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.preference.PreferenceManager;
+
+import org.briarproject.bramble.api.account.AccountManager;
+import org.briarproject.bramble.api.crypto.CryptoComponent;
+import org.briarproject.bramble.api.db.DatabaseConfig;
+import org.briarproject.bramble.api.identity.IdentityManager;
+
+import java.io.File;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.GuardedBy;
+import javax.inject.Inject;
+
+import static android.os.Build.VERSION.SDK_INT;
+import static java.util.Arrays.asList;
+import static java.util.logging.Level.INFO;
+import static org.briarproject.bramble.util.IoUtils.deleteFileOrDir;
+import static org.briarproject.bramble.util.LogUtils.logFileOrDir;
+
+class AndroidAccountManager extends AccountManagerImpl
+		implements AccountManager {
+
+	private static final Logger LOG =
+			Logger.getLogger(AndroidAccountManager.class.getName());
+
+	/**
+	 * Directories that shouldn't be deleted when deleting the user's account.
+	 */
+	private static final List<String> PROTECTED_DIR_NAMES =
+			asList("cache", "code_cache", "lib", "shared_prefs");
+
+	protected final Context appContext;
+	private final SharedPreferences prefs;
+
+	@Inject
+	AndroidAccountManager(DatabaseConfig databaseConfig,
+			CryptoComponent crypto, IdentityManager identityManager,
+			SharedPreferences prefs, Application app) {
+		super(databaseConfig, crypto, identityManager);
+		this.prefs = prefs;
+		appContext = app.getApplicationContext();
+	}
+
+	@Override
+	public boolean accountExists() {
+		boolean exists = super.accountExists();
+		if (!exists && LOG.isLoggable(INFO)) {
+			LOG.info("Account does not exist. Contents of account directory:");
+			logFileOrDir(LOG, INFO, getDataDir());
+		}
+		return exists;
+	}
+
+	@Override
+	public void deleteAccount() {
+		synchronized (stateChangeLock) {
+			if (LOG.isLoggable(INFO)) {
+				LOG.info("Contents of account directory before deleting:");
+				logFileOrDir(LOG, INFO, getDataDir());
+			}
+			super.deleteAccount();
+			SharedPreferences defaultPrefs = getDefaultSharedPreferences();
+			deleteAppData(prefs, defaultPrefs);
+			if (LOG.isLoggable(INFO)) {
+				LOG.info("Contents of account directory after deleting:");
+				logFileOrDir(LOG, INFO, getDataDir());
+			}
+		}
+	}
+
+	// Package access for testing
+	SharedPreferences getDefaultSharedPreferences() {
+		return PreferenceManager.getDefaultSharedPreferences(appContext);
+	}
+
+	@GuardedBy("stateChangeLock")
+	private void deleteAppData(SharedPreferences... clear) {
+		// Clear and commit shared preferences
+		for (SharedPreferences prefs : clear) {
+			if (!prefs.edit().clear().commit())
+				LOG.warning("Could not clear shared preferences");
+		}
+		// Delete files, except protected directories
+		Set<File> files = new HashSet<>();
+		File dataDir = getDataDir();
+		@Nullable
+		File[] fileArray = dataDir.listFiles();
+		if (fileArray == null) {
+			LOG.warning("Could not list files in app data dir");
+		} else {
+			for (File file : fileArray) {
+				if (!PROTECTED_DIR_NAMES.contains(file.getName())) {
+					files.add(file);
+				}
+			}
+		}
+		files.add(appContext.getFilesDir());
+		addIfNotNull(files, appContext.getExternalCacheDir());
+		if (SDK_INT >= 19) {
+			for (File file : appContext.getExternalCacheDirs()) {
+				addIfNotNull(files, file);
+			}
+		}
+		if (SDK_INT >= 21) {
+			for (File file : appContext.getExternalMediaDirs()) {
+				addIfNotNull(files, file);
+			}
+		}
+		// Clear the cache directory but don't delete it
+		File cacheDir = appContext.getCacheDir();
+		File[] children = cacheDir.listFiles();
+		if (children != null) files.addAll(asList(children));
+		for (File file : files) {
+			if (LOG.isLoggable(INFO)) {
+				LOG.info("Deleting " + file.getAbsolutePath());
+			}
+			deleteFileOrDir(file);
+		}
+	}
+
+	private File getDataDir() {
+		return new File(appContext.getApplicationInfo().dataDir);
+	}
+
+	private void addIfNotNull(Set<File> files, @Nullable File file) {
+		if (file != null) files.add(file);
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/api/system/AlarmListener.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/api/system/AlarmListener.java
@@ -0,0 +1,11 @@
+package org.briarproject.bramble.api.system;
+
+import android.content.Intent;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface AlarmListener {
+
+	void onAlarm(Intent intent);
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/api/system/AndroidWakeLock.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/api/system/AndroidWakeLock.java
@@ -0,0 +1,19 @@
+package org.briarproject.bramble.api.system;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface AndroidWakeLock {
+
+	/**
+	 * Acquires the wake lock. This has no effect if the wake lock has already
+	 * been acquired.
+	 */
+	void acquire();
+
+	/**
+	 * Releases the wake lock. This has no effect if the wake lock has already
+	 * been released.
+	 */
+	void release();
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/api/system/AndroidWakeLockManager.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/api/system/AndroidWakeLockManager.java
@@ -0,0 +1,38 @@
+package org.briarproject.bramble.api.system;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.util.concurrent.Executor;
+
+@NotNullByDefault
+public interface AndroidWakeLockManager {
+
+	/**
+	 * Creates a wake lock with the given tag. The tag is only used for
+	 * logging; the underlying OS wake lock will use its own tag.
+	 */
+	AndroidWakeLock createWakeLock(String tag);
+
+	/**
+	 * Runs the given task while holding a wake lock.
+	 */
+	void runWakefully(Runnable r, String tag);
+
+	/**
+	 * Submits the given task to the given executor while holding a wake lock.
+	 * The lock is released when the task completes, or if an exception is
+	 * thrown while submitting or running the task.
+	 */
+	void executeWakefully(Runnable r, Executor executor, String tag);
+
+	/**
+	 * Starts a dedicated thread to run the given task asynchronously. A wake
+	 * lock is acquired before starting the thread and released when the task
+	 * completes, or if an exception is thrown while starting the thread or
+	 * running the task.
+	 * <p>
+	 * This method should only be used for lifecycle management tasks that
+	 * can't be run on an executor.
+	 */
+	void executeWakefully(Runnable r, String tag);
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/battery/AndroidBatteryManager.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/battery/AndroidBatteryManager.java
@@ -0,0 +1,81 @@
+package org.briarproject.bramble.battery;
+
+import android.app.Application;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+
+import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.battery.event.BatteryEvent;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.lifecycle.Service;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.logging.Logger;
+
+import javax.inject.Inject;
+
+import static android.content.Intent.ACTION_BATTERY_CHANGED;
+import static android.content.Intent.ACTION_POWER_CONNECTED;
+import static android.content.Intent.ACTION_POWER_DISCONNECTED;
+import static android.os.BatteryManager.EXTRA_PLUGGED;
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Logger.getLogger;
+
+class AndroidBatteryManager implements BatteryManager, Service {
+
+	private static final Logger LOG =
+			getLogger(AndroidBatteryManager.class.getName());
+
+	private final Context appContext;
+	private final EventBus eventBus;
+	private final AtomicBoolean used = new AtomicBoolean(false);
+
+	private volatile BroadcastReceiver batteryReceiver = null;
+
+	@Inject
+	AndroidBatteryManager(Application app, EventBus eventBus) {
+		this.appContext = app.getApplicationContext();
+		this.eventBus = eventBus;
+	}
+
+	@Override
+	public boolean isCharging() {
+		// Get the sticky intent for ACTION_BATTERY_CHANGED
+		IntentFilter filter = new IntentFilter(ACTION_BATTERY_CHANGED);
+		Intent i = appContext.registerReceiver(null, filter);
+		if (i == null) return false;
+		int status = i.getIntExtra(EXTRA_PLUGGED, 0);
+		return status != 0;
+	}
+
+	@Override
+	public void startService() {
+		if (used.getAndSet(true)) throw new IllegalStateException();
+		batteryReceiver = new BatteryReceiver();
+		IntentFilter filter = new IntentFilter();
+		filter.addAction(ACTION_POWER_CONNECTED);
+		filter.addAction(ACTION_POWER_DISCONNECTED);
+		appContext.registerReceiver(batteryReceiver, filter);
+	}
+
+	@Override
+	public void stopService() {
+		if (batteryReceiver != null)
+			appContext.unregisterReceiver(batteryReceiver);
+	}
+
+	private class BatteryReceiver extends BroadcastReceiver {
+
+		@Override
+		public void onReceive(Context ctx, Intent i) {
+			String action = i.getAction();
+			if (LOG.isLoggable(INFO)) LOG.info("Received broadcast " + action);
+			if (ACTION_POWER_CONNECTED.equals(action))
+				eventBus.broadcast(new BatteryEvent(true));
+			else if (ACTION_POWER_DISCONNECTED.equals(action))
+				eventBus.broadcast(new BatteryEvent(false));
+		}
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/battery/AndroidBatteryModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/battery/AndroidBatteryModule.java
@@ -0,0 +1,27 @@
+package org.briarproject.bramble.battery;
+
+import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class AndroidBatteryModule {
+
+	public static class EagerSingletons {
+		@Inject
+		BatteryManager batteryManager;
+	}
+
+	@Provides
+	@Singleton
+	BatteryManager provideBatteryManager(LifecycleManager lifecycleManager,
+			AndroidBatteryManager batteryManager) {
+		lifecycleManager.registerService(batteryManager);
+		return batteryManager;
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/network/AndroidNetworkManager.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/network/AndroidNetworkManager.java
@@ -0,0 +1,224 @@
+package org.briarproject.bramble.network;
+
+import android.annotation.TargetApi;
+import android.app.Application;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.ConnectivityManager;
+import android.net.LinkAddress;
+import android.net.LinkProperties;
+import android.net.Network;
+import android.net.NetworkInfo;
+
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.event.EventExecutor;
+import org.briarproject.bramble.api.lifecycle.Service;
+import org.briarproject.bramble.api.network.NetworkManager;
+import org.briarproject.bramble.api.network.NetworkStatus;
+import org.briarproject.bramble.api.network.event.NetworkStatusEvent;
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
+import org.briarproject.bramble.api.system.TaskScheduler;
+import org.briarproject.bramble.api.system.TaskScheduler.Cancellable;
+
+import java.net.Inet4Address;
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.util.Enumeration;
+import java.util.concurrent.Executor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+import javax.inject.Inject;
+
+import static android.content.Context.CONNECTIVITY_SERVICE;
+import static android.content.Intent.ACTION_SCREEN_OFF;
+import static android.content.Intent.ACTION_SCREEN_ON;
+import static android.net.ConnectivityManager.CONNECTIVITY_ACTION;
+import static android.net.ConnectivityManager.TYPE_WIFI;
+import static android.net.wifi.p2p.WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION;
+import static android.os.Build.VERSION.SDK_INT;
+import static android.os.PowerManager.ACTION_DEVICE_IDLE_MODE_CHANGED;
+import static java.net.NetworkInterface.getNetworkInterfaces;
+import static java.util.Collections.list;
+import static java.util.concurrent.TimeUnit.MINUTES;
+import static java.util.concurrent.TimeUnit.SECONDS;
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+import static org.briarproject.bramble.util.LogUtils.logException;
+
+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
+class AndroidNetworkManager implements NetworkManager, Service {
+
+	private static final Logger LOG =
+			getLogger(AndroidNetworkManager.class.getName());
+
+	// See android.net.wifi.WifiManager
+	private static final String WIFI_AP_STATE_CHANGED_ACTION =
+			"android.net.wifi.WIFI_AP_STATE_CHANGED";
+
+	private final TaskScheduler scheduler;
+	private final EventBus eventBus;
+	private final Executor eventExecutor;
+	private final Application app;
+	private final ConnectivityManager connectivityManager;
+	private final AtomicReference<Cancellable> connectivityCheck =
+			new AtomicReference<>();
+	private final AtomicBoolean used = new AtomicBoolean(false);
+
+	private volatile BroadcastReceiver networkStateReceiver = null;
+
+	@Inject
+	AndroidNetworkManager(TaskScheduler scheduler, EventBus eventBus,
+			@EventExecutor Executor eventExecutor, Application app) {
+		this.scheduler = scheduler;
+		this.eventBus = eventBus;
+		this.eventExecutor = eventExecutor;
+		this.app = app;
+		connectivityManager = (ConnectivityManager)
+				requireNonNull(app.getSystemService(CONNECTIVITY_SERVICE));
+	}
+
+	@Override
+	public void startService() {
+		if (used.getAndSet(true)) throw new IllegalStateException();
+		// Register to receive network status events
+		networkStateReceiver = new NetworkStateReceiver();
+		IntentFilter filter = new IntentFilter();
+		filter.addAction(CONNECTIVITY_ACTION);
+		filter.addAction(ACTION_SCREEN_ON);
+		filter.addAction(ACTION_SCREEN_OFF);
+		filter.addAction(WIFI_AP_STATE_CHANGED_ACTION);
+		filter.addAction(WIFI_P2P_THIS_DEVICE_CHANGED_ACTION);
+		if (SDK_INT >= 23) filter.addAction(ACTION_DEVICE_IDLE_MODE_CHANGED);
+		app.registerReceiver(networkStateReceiver, filter);
+	}
+
+	@Override
+	public void stopService() {
+		if (networkStateReceiver != null)
+			app.unregisterReceiver(networkStateReceiver);
+	}
+
+	@Override
+	public NetworkStatus getNetworkStatus() {
+		NetworkInfo net = connectivityManager.getActiveNetworkInfo();
+		boolean connected = net != null && net.isConnected();
+		boolean wifi = false, ipv6Only = false;
+		if (connected) {
+			wifi = net.getType() == TYPE_WIFI;
+			if (SDK_INT >= 23) ipv6Only = isActiveNetworkIpv6Only();
+			else ipv6Only = areAllAvailableNetworksIpv6Only();
+		}
+		return new NetworkStatus(connected, wifi, ipv6Only);
+	}
+
+	/**
+	 * Returns true if the
+	 * {@link ConnectivityManager#getActiveNetwork() active network} has an
+	 * IPv6 unicast address and no IPv4 addresses. The active network is
+	 * assumed not to be a loopback interface.
+	 */
+	@TargetApi(23)
+	private boolean isActiveNetworkIpv6Only() {
+		Network net = connectivityManager.getActiveNetwork();
+		if (net == null) {
+			LOG.info("No active network");
+			return false;
+		}
+		LinkProperties props = connectivityManager.getLinkProperties(net);
+		if (props == null) {
+			LOG.info("No link properties for active network");
+			return false;
+		}
+		boolean hasIpv6Unicast = false;
+		for (LinkAddress linkAddress : props.getLinkAddresses()) {
+			InetAddress addr = linkAddress.getAddress();
+			if (addr instanceof Inet4Address) return false;
+			if (!addr.isMulticastAddress()) hasIpv6Unicast = true;
+		}
+		return hasIpv6Unicast;
+	}
+
+	/**
+	 * Returns true if the device has at least one network interface with an
+	 * IPv6 unicast address and no interfaces with IPv4 addresses, excluding
+	 * loopback interfaces and interfaces that are
+	 * {@link NetworkInterface#isUp() down}. If this method returns true and
+	 * the device has internet access then it's via IPv6 only.
+	 */
+	private boolean areAllAvailableNetworksIpv6Only() {
+		try {
+			Enumeration<NetworkInterface> interfaces = getNetworkInterfaces();
+			if (interfaces == null) {
+				LOG.info("No network interfaces");
+				return false;
+			}
+			boolean hasIpv6Unicast = false;
+			for (NetworkInterface i : list(interfaces)) {
+				if (i.isLoopback() || !i.isUp()) continue;
+				for (InetAddress addr : list(i.getInetAddresses())) {
+					if (addr instanceof Inet4Address) return false;
+					if (!addr.isMulticastAddress()) hasIpv6Unicast = true;
+				}
+			}
+			return hasIpv6Unicast;
+		} catch (SocketException e) {
+			logException(LOG, WARNING, e);
+			return false;
+		}
+	}
+
+	private void updateConnectionStatus() {
+		eventBus.broadcast(new NetworkStatusEvent(getNetworkStatus()));
+	}
+
+	private void scheduleConnectionStatusUpdate(int delay, TimeUnit unit) {
+		Cancellable newConnectivityCheck =
+				scheduler.schedule(this::updateConnectionStatus, eventExecutor,
+						delay, unit);
+		Cancellable oldConnectivityCheck =
+				connectivityCheck.getAndSet(newConnectivityCheck);
+		if (oldConnectivityCheck != null) oldConnectivityCheck.cancel();
+	}
+
+	private class NetworkStateReceiver extends BroadcastReceiver {
+
+		@Override
+		public void onReceive(Context ctx, Intent i) {
+			String action = i.getAction();
+			if (LOG.isLoggable(INFO)) LOG.info("Received broadcast " + action);
+			updateConnectionStatus();
+			if (isSleepOrDozeEvent(action)) {
+				// Allow time for the network to be enabled or disabled
+				scheduleConnectionStatusUpdate(1, MINUTES);
+			} else if (isApEvent(action)) {
+				// The state change may be broadcast before the AP address is
+				// visible, so delay handling the event
+				scheduleConnectionStatusUpdate(5, SECONDS);
+			}
+		}
+
+		private boolean isSleepOrDozeEvent(@Nullable String action) {
+			boolean isSleep = ACTION_SCREEN_ON.equals(action) ||
+					ACTION_SCREEN_OFF.equals(action);
+			boolean isDoze = SDK_INT >= 23 &&
+					ACTION_DEVICE_IDLE_MODE_CHANGED.equals(action);
+			return isSleep || isDoze;
+		}
+
+		private boolean isApEvent(@Nullable String action) {
+			return WIFI_AP_STATE_CHANGED_ACTION.equals(action) ||
+					WIFI_P2P_THIS_DEVICE_CHANGED_ACTION.equals(action);
+		}
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/network/AndroidNetworkModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/network/AndroidNetworkModule.java
@@ -0,0 +1,27 @@
+package org.briarproject.bramble.network;
+
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+import org.briarproject.bramble.api.network.NetworkManager;
+
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class AndroidNetworkModule {
+
+	public static class EagerSingletons {
+		@Inject
+		NetworkManager networkManager;
+	}
+
+	@Provides
+	@Singleton
+	NetworkManager provideNetworkManager(LifecycleManager lifecycleManager,
+			AndroidNetworkManager networkManager) {
+		lifecycleManager.registerService(networkManager);
+		return networkManager;
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/AndroidPluginModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/AndroidPluginModule.java
@@ -1,65 +0,0 @@
-package org.briarproject.bramble.plugin;
-
-import android.app.Application;
-import android.content.Context;
-
-import org.briarproject.bramble.api.event.EventBus;
-import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.plugin.BackoffFactory;
-import org.briarproject.bramble.api.plugin.PluginConfig;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
-import org.briarproject.bramble.api.plugin.simplex.SimplexPluginFactory;
-import org.briarproject.bramble.api.reporting.DevReporter;
-import org.briarproject.bramble.api.system.AndroidExecutor;
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.plugin.droidtooth.DroidtoothPluginFactory;
-import org.briarproject.bramble.plugin.tcp.AndroidLanTcpPluginFactory;
-import org.briarproject.bramble.plugin.tor.TorPluginFactory;
-
-import java.security.SecureRandom;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.concurrent.Executor;
-
-import javax.net.SocketFactory;
-
-import dagger.Module;
-import dagger.Provides;
-
-@Module
-public class AndroidPluginModule {
-
-	@Provides
-	PluginConfig providePluginConfig(@IoExecutor Executor ioExecutor,
-			AndroidExecutor androidExecutor, SecureRandom random,
-			SocketFactory torSocketFactory, BackoffFactory backoffFactory,
-			Application app, LocationUtils locationUtils, DevReporter reporter,
-			EventBus eventBus) {
-		Context appContext = app.getApplicationContext();
-		DuplexPluginFactory bluetooth = new DroidtoothPluginFactory(ioExecutor,
-				androidExecutor, appContext, random, backoffFactory);
-		DuplexPluginFactory tor = new TorPluginFactory(ioExecutor, appContext,
-				locationUtils, reporter, eventBus, torSocketFactory,
-				backoffFactory);
-		DuplexPluginFactory lan = new AndroidLanTcpPluginFactory(ioExecutor,
-				backoffFactory, appContext);
-		final Collection<DuplexPluginFactory> duplex =
-				Arrays.asList(bluetooth, tor, lan);
-		@NotNullByDefault
-		PluginConfig pluginConfig = new PluginConfig() {
-
-			@Override
-			public Collection<DuplexPluginFactory> getDuplexFactories() {
-				return duplex;
-			}
-
-			@Override
-			public Collection<SimplexPluginFactory> getSimplexFactories() {
-				return Collections.emptyList();
-			}
-		};
-		return pluginConfig;
-	}
-}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothConnectionFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothConnectionFactory.java
@@ -0,0 +1,36 @@
+package org.briarproject.bramble.plugin.bluetooth;
+
+import android.bluetooth.BluetoothSocket;
+
+import org.briarproject.bramble.api.io.TimeoutMonitor;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
+import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+
+import java.io.IOException;
+
+@NotNullByDefault
+class AndroidBluetoothConnectionFactory
+		implements BluetoothConnectionFactory<BluetoothSocket> {
+
+	private final BluetoothConnectionLimiter connectionLimiter;
+	private final AndroidWakeLockManager wakeLockManager;
+	private final TimeoutMonitor timeoutMonitor;
+
+	AndroidBluetoothConnectionFactory(
+			BluetoothConnectionLimiter connectionLimiter,
+			AndroidWakeLockManager wakeLockManager,
+			TimeoutMonitor timeoutMonitor) {
+		this.connectionLimiter = connectionLimiter;
+		this.wakeLockManager = wakeLockManager;
+		this.timeoutMonitor = timeoutMonitor;
+	}
+
+	@Override
+	public DuplexTransportConnection wrapSocket(DuplexPlugin plugin,
+			BluetoothSocket s) throws IOException {
+		return new AndroidBluetoothTransportConnection(plugin,
+				connectionLimiter, wakeLockManager, timeoutMonitor, s);
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPlugin.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPlugin.java
@@ -0,0 +1,289 @@
+package org.briarproject.bramble.plugin.bluetooth;
+
+import android.app.Application;
+import android.bluetooth.BluetoothAdapter;
+import android.bluetooth.BluetoothDevice;
+import android.bluetooth.BluetoothServerSocket;
+import android.bluetooth.BluetoothSocket;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
+import org.briarproject.bramble.api.plugin.Backoff;
+import org.briarproject.bramble.api.plugin.PluginCallback;
+import org.briarproject.bramble.api.plugin.PluginException;
+import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
+import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.bramble.util.AndroidUtils;
+import org.briarproject.bramble.util.IoUtils;
+
+import java.io.IOException;
+import java.security.SecureRandom;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+
+import static android.bluetooth.BluetoothAdapter.ACTION_DISCOVERY_FINISHED;
+import static android.bluetooth.BluetoothAdapter.ACTION_DISCOVERY_STARTED;
+import static android.bluetooth.BluetoothAdapter.ACTION_SCAN_MODE_CHANGED;
+import static android.bluetooth.BluetoothAdapter.ACTION_STATE_CHANGED;
+import static android.bluetooth.BluetoothAdapter.EXTRA_SCAN_MODE;
+import static android.bluetooth.BluetoothAdapter.EXTRA_STATE;
+import static android.bluetooth.BluetoothAdapter.SCAN_MODE_CONNECTABLE;
+import static android.bluetooth.BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE;
+import static android.bluetooth.BluetoothAdapter.SCAN_MODE_NONE;
+import static android.bluetooth.BluetoothAdapter.STATE_OFF;
+import static android.bluetooth.BluetoothAdapter.STATE_ON;
+import static android.bluetooth.BluetoothDevice.ACTION_FOUND;
+import static android.bluetooth.BluetoothDevice.DEVICE_TYPE_LE;
+import static android.bluetooth.BluetoothDevice.EXTRA_DEVICE;
+import static android.os.Build.VERSION.SDK_INT;
+import static java.util.Collections.shuffle;
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.util.PrivacyUtils.scrubMacAddress;
+
+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
+class AndroidBluetoothPlugin
+		extends BluetoothPlugin<BluetoothSocket, BluetoothServerSocket> {
+
+	private static final Logger LOG =
+			getLogger(AndroidBluetoothPlugin.class.getName());
+
+	private static final int MAX_DISCOVERY_MS = 10_000;
+
+	private final AndroidExecutor androidExecutor;
+	private final Application app;
+	private final Clock clock;
+
+	private volatile BluetoothStateReceiver receiver = null;
+
+	// Non-null if the plugin started successfully
+	private volatile BluetoothAdapter adapter = null;
+
+	AndroidBluetoothPlugin(BluetoothConnectionLimiter connectionLimiter,
+			BluetoothConnectionFactory<BluetoothSocket> connectionFactory,
+			Executor ioExecutor,
+			Executor wakefulIoExecutor,
+			SecureRandom secureRandom,
+			AndroidExecutor androidExecutor,
+			Application app,
+			Clock clock,
+			Backoff backoff,
+			PluginCallback callback,
+			int maxLatency,
+			int maxIdleTime) {
+		super(connectionLimiter, connectionFactory, ioExecutor,
+				wakefulIoExecutor, secureRandom, backoff, callback,
+				maxLatency, maxIdleTime);
+		this.androidExecutor = androidExecutor;
+		this.app = app;
+		this.clock = clock;
+	}
+
+	@Override
+	public void start() throws PluginException {
+		super.start();
+		// Listen for changes to the Bluetooth state
+		IntentFilter filter = new IntentFilter();
+		filter.addAction(ACTION_STATE_CHANGED);
+		filter.addAction(ACTION_SCAN_MODE_CHANGED);
+		receiver = new BluetoothStateReceiver();
+		app.registerReceiver(receiver, filter);
+	}
+
+	@Override
+	public void stop() {
+		super.stop();
+		if (receiver != null) app.unregisterReceiver(receiver);
+	}
+
+	@Override
+	void initialiseAdapter() throws IOException {
+		// BluetoothAdapter.getDefaultAdapter() must be called on a thread
+		// with a message queue, so submit it to the AndroidExecutor
+		try {
+			adapter = androidExecutor.runOnBackgroundThread(
+					BluetoothAdapter::getDefaultAdapter).get();
+		} catch (InterruptedException | ExecutionException e) {
+			throw new IOException(e);
+		}
+		if (adapter == null)
+			throw new IOException("Bluetooth is not supported");
+	}
+
+	@Override
+	boolean isAdapterEnabled() {
+		return adapter != null && adapter.isEnabled();
+	}
+
+	@Override
+	@Nullable
+	String getBluetoothAddress() {
+		if (adapter == null) return null;
+		String address = AndroidUtils.getBluetoothAddress(app, adapter);
+		return address.isEmpty() ? null : address;
+	}
+
+	@Override
+	BluetoothServerSocket openServerSocket(String uuid) throws IOException {
+		return adapter.listenUsingInsecureRfcommWithServiceRecord(
+				"RFCOMM", UUID.fromString(uuid));
+	}
+
+	@Override
+	void tryToClose(@Nullable BluetoothServerSocket ss) {
+		IoUtils.tryToClose(ss, LOG, WARNING);
+	}
+
+	@Override
+	DuplexTransportConnection acceptConnection(BluetoothServerSocket ss)
+			throws IOException {
+		return connectionFactory.wrapSocket(this, ss.accept());
+	}
+
+	@Override
+	boolean isValidAddress(String address) {
+		return BluetoothAdapter.checkBluetoothAddress(address);
+	}
+
+	@Override
+	DuplexTransportConnection connectTo(String address, String uuid)
+			throws IOException {
+		BluetoothDevice d = adapter.getRemoteDevice(address);
+		UUID u = UUID.fromString(uuid);
+		BluetoothSocket s = null;
+		try {
+			s = d.createInsecureRfcommSocketToServiceRecord(u);
+			s.connect();
+			return connectionFactory.wrapSocket(this, s);
+		} catch (IOException e) {
+			IoUtils.tryToClose(s, LOG, WARNING);
+			throw e;
+		} catch (NullPointerException e) {
+			// BluetoothSocket#connect() may throw an NPE under unknown
+			// circumstances
+			IoUtils.tryToClose(s, LOG, WARNING);
+			throw new IOException(e);
+		}
+	}
+
+	@Override
+	@Nullable
+	DuplexTransportConnection discoverAndConnect(String uuid) {
+		if (adapter == null) return null;
+		for (String address : discoverDevices()) {
+			try {
+				if (LOG.isLoggable(INFO))
+					LOG.info("Connecting to " + scrubMacAddress(address));
+				return connectTo(address, uuid);
+			} catch (IOException e) {
+				if (LOG.isLoggable(INFO)) {
+					LOG.info("Could not connect to "
+							+ scrubMacAddress(address));
+				}
+			}
+		}
+		LOG.info("Could not connect to any devices");
+		return null;
+	}
+
+	private Collection<String> discoverDevices() {
+		List<String> addresses = new ArrayList<>();
+		BlockingQueue<Intent> intents = new LinkedBlockingQueue<>();
+		DiscoveryReceiver receiver = new DiscoveryReceiver(intents);
+		IntentFilter filter = new IntentFilter();
+		filter.addAction(ACTION_DISCOVERY_STARTED);
+		filter.addAction(ACTION_DISCOVERY_FINISHED);
+		filter.addAction(ACTION_FOUND);
+		app.registerReceiver(receiver, filter);
+		try {
+			if (adapter.startDiscovery()) {
+				long now = clock.currentTimeMillis();
+				long end = now + MAX_DISCOVERY_MS;
+				while (now < end) {
+					Intent i = intents.poll(end - now, MILLISECONDS);
+					if (i == null) break;
+					String action = i.getAction();
+					if (ACTION_DISCOVERY_STARTED.equals(action)) {
+						LOG.info("Discovery started");
+					} else if (ACTION_DISCOVERY_FINISHED.equals(action)) {
+						LOG.info("Discovery finished");
+						break;
+					} else if (ACTION_FOUND.equals(action)) {
+						BluetoothDevice d = i.getParcelableExtra(EXTRA_DEVICE);
+						// Ignore Bluetooth LE devices
+						if (SDK_INT < 18 || d.getType() != DEVICE_TYPE_LE) {
+							String address = d.getAddress();
+							if (LOG.isLoggable(INFO))
+								LOG.info("Discovered " +
+										scrubMacAddress(address));
+							if (!addresses.contains(address))
+								addresses.add(address);
+						}
+					}
+					now = clock.currentTimeMillis();
+				}
+			} else {
+				LOG.info("Could not start discovery");
+			}
+		} catch (InterruptedException e) {
+			LOG.info("Interrupted while discovering devices");
+			Thread.currentThread().interrupt();
+		} finally {
+			LOG.info("Cancelling discovery");
+			adapter.cancelDiscovery();
+			app.unregisterReceiver(receiver);
+		}
+		// Shuffle the addresses so we don't always try the same one first
+		shuffle(addresses);
+		return addresses;
+	}
+
+	private class BluetoothStateReceiver extends BroadcastReceiver {
+
+		@Override
+		public void onReceive(Context ctx, Intent intent) {
+			int state = intent.getIntExtra(EXTRA_STATE, 0);
+			if (state == STATE_ON) onAdapterEnabled();
+			else if (state == STATE_OFF) onAdapterDisabled();
+			int scanMode = intent.getIntExtra(EXTRA_SCAN_MODE, 0);
+			if (scanMode == SCAN_MODE_NONE) {
+				LOG.info("Scan mode: None");
+			} else if (scanMode == SCAN_MODE_CONNECTABLE) {
+				LOG.info("Scan mode: Connectable");
+			} else if (scanMode == SCAN_MODE_CONNECTABLE_DISCOVERABLE) {
+				LOG.info("Scan mode: Discoverable");
+			}
+		}
+	}
+
+	private static class DiscoveryReceiver extends BroadcastReceiver {
+
+		private final BlockingQueue<Intent> intents;
+
+		private DiscoveryReceiver(BlockingQueue<Intent> intents) {
+			this.intents = intents;
+		}
+
+		@Override
+		public void onReceive(Context ctx, Intent intent) {
+			intents.add(intent);
+		}
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPluginFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPluginFactory.java
@@ -0,0 +1,98 @@
+package org.briarproject.bramble.plugin.bluetooth;
+
+import android.app.Application;
+import android.bluetooth.BluetoothSocket;
+
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.io.TimeoutMonitor;
+import org.briarproject.bramble.api.lifecycle.IoExecutor;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.Backoff;
+import org.briarproject.bramble.api.plugin.BackoffFactory;
+import org.briarproject.bramble.api.plugin.PluginCallback;
+import org.briarproject.bramble.api.plugin.TransportId;
+import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
+import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
+import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.bramble.api.system.WakefulIoExecutor;
+
+import java.security.SecureRandom;
+import java.util.concurrent.Executor;
+
+import javax.annotation.concurrent.Immutable;
+import javax.inject.Inject;
+
+import static org.briarproject.bramble.api.plugin.BluetoothConstants.ID;
+
+@Immutable
+@NotNullByDefault
+public class AndroidBluetoothPluginFactory implements DuplexPluginFactory {
+
+	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
+	private static final int MAX_IDLE_TIME = 30 * 1000; // 30 seconds
+	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
+	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
+	private static final double BACKOFF_BASE = 1.2;
+
+	private final Executor ioExecutor, wakefulIoExecutor;
+	private final AndroidExecutor androidExecutor;
+	private final AndroidWakeLockManager wakeLockManager;
+	private final Application app;
+	private final SecureRandom secureRandom;
+	private final EventBus eventBus;
+	private final Clock clock;
+	private final TimeoutMonitor timeoutMonitor;
+	private final BackoffFactory backoffFactory;
+
+	@Inject
+	public AndroidBluetoothPluginFactory(@IoExecutor Executor ioExecutor,
+			@WakefulIoExecutor Executor wakefulIoExecutor,
+			AndroidExecutor androidExecutor,
+			AndroidWakeLockManager wakeLockManager,
+			Application app,
+			SecureRandom secureRandom,
+			EventBus eventBus,
+			Clock clock,
+			TimeoutMonitor timeoutMonitor,
+			BackoffFactory backoffFactory) {
+		this.ioExecutor = ioExecutor;
+		this.wakefulIoExecutor = wakefulIoExecutor;
+		this.androidExecutor = androidExecutor;
+		this.wakeLockManager = wakeLockManager;
+		this.app = app;
+		this.secureRandom = secureRandom;
+		this.eventBus = eventBus;
+		this.clock = clock;
+		this.timeoutMonitor = timeoutMonitor;
+		this.backoffFactory = backoffFactory;
+	}
+
+	@Override
+	public TransportId getId() {
+		return ID;
+	}
+
+	@Override
+	public int getMaxLatency() {
+		return MAX_LATENCY;
+	}
+
+	@Override
+	public DuplexPlugin createPlugin(PluginCallback callback) {
+		BluetoothConnectionLimiter connectionLimiter =
+				new BluetoothConnectionLimiterImpl(eventBus);
+		BluetoothConnectionFactory<BluetoothSocket> connectionFactory =
+				new AndroidBluetoothConnectionFactory(connectionLimiter,
+						wakeLockManager, timeoutMonitor);
+		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
+				MAX_POLLING_INTERVAL, BACKOFF_BASE);
+		AndroidBluetoothPlugin plugin = new AndroidBluetoothPlugin(
+				connectionLimiter, connectionFactory, ioExecutor,
+				wakefulIoExecutor, secureRandom, androidExecutor, app,
+				clock, backoff, callback, MAX_LATENCY, MAX_IDLE_TIME);
+		eventBus.addListener(plugin);
+		return plugin;
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothTransportConnection.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothTransportConnection.java
@@ -0,0 +1,64 @@
+package org.briarproject.bramble.plugin.bluetooth;
+
+import android.bluetooth.BluetoothSocket;
+
+import org.briarproject.bramble.api.io.TimeoutMonitor;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.Plugin;
+import org.briarproject.bramble.api.plugin.duplex.AbstractDuplexTransportConnection;
+import org.briarproject.bramble.api.system.AndroidWakeLock;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_ADDRESS;
+import static org.briarproject.bramble.util.AndroidUtils.isValidBluetoothAddress;
+
+@NotNullByDefault
+class AndroidBluetoothTransportConnection
+		extends AbstractDuplexTransportConnection {
+
+	private final BluetoothConnectionLimiter connectionLimiter;
+	private final BluetoothSocket socket;
+	private final InputStream in;
+	private final AndroidWakeLock wakeLock;
+
+	AndroidBluetoothTransportConnection(Plugin plugin,
+			BluetoothConnectionLimiter connectionLimiter,
+			AndroidWakeLockManager wakeLockManager,
+			TimeoutMonitor timeoutMonitor,
+			BluetoothSocket socket) throws IOException {
+		super(plugin);
+		this.connectionLimiter = connectionLimiter;
+		this.socket = socket;
+		in = timeoutMonitor.createTimeoutInputStream(
+				socket.getInputStream(), plugin.getMaxIdleTime() * 2);
+		wakeLock = wakeLockManager.createWakeLock("BluetoothConnection");
+		wakeLock.acquire();
+		String address = socket.getRemoteDevice().getAddress();
+		if (isValidBluetoothAddress(address)) remote.put(PROP_ADDRESS, address);
+	}
+
+	@Override
+	protected InputStream getInputStream() {
+		return in;
+	}
+
+	@Override
+	protected OutputStream getOutputStream() throws IOException {
+		return socket.getOutputStream();
+	}
+
+	@Override
+	protected void closeConnection(boolean exception) throws IOException {
+		try {
+			socket.close();
+			in.close();
+		} finally {
+			wakeLock.release();
+			connectionLimiter.connectionClosed(this);
+		}
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/droidtooth/DroidtoothPlugin.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/droidtooth/DroidtoothPlugin.java
@@ -1,682 +0,0 @@
-package org.briarproject.bramble.plugin.droidtooth;
-
-import android.bluetooth.BluetoothAdapter;
-import android.bluetooth.BluetoothDevice;
-import android.bluetooth.BluetoothServerSocket;
-import android.bluetooth.BluetoothSocket;
-import android.content.BroadcastReceiver;
-import android.content.Context;
-import android.content.Intent;
-import android.content.IntentFilter;
-
-import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.crypto.PseudoRandom;
-import org.briarproject.bramble.api.data.BdfList;
-import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
-import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
-import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
-import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
-import org.briarproject.bramble.api.plugin.Backoff;
-import org.briarproject.bramble.api.plugin.PluginException;
-import org.briarproject.bramble.api.plugin.TransportId;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
-import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
-import org.briarproject.bramble.api.properties.TransportProperties;
-import org.briarproject.bramble.api.system.AndroidExecutor;
-import org.briarproject.bramble.util.AndroidUtils;
-import org.briarproject.bramble.util.StringUtils;
-
-import java.io.Closeable;
-import java.io.IOException;
-import java.io.InputStream;
-import java.security.SecureRandom;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.UUID;
-import java.util.concurrent.Callable;
-import java.util.concurrent.CompletionService;
-import java.util.concurrent.CopyOnWriteArrayList;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.Executor;
-import java.util.concurrent.ExecutorCompletionService;
-import java.util.concurrent.Future;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.logging.Logger;
-
-import javax.annotation.Nullable;
-
-import static android.bluetooth.BluetoothAdapter.ACTION_SCAN_MODE_CHANGED;
-import static android.bluetooth.BluetoothAdapter.ACTION_STATE_CHANGED;
-import static android.bluetooth.BluetoothAdapter.EXTRA_SCAN_MODE;
-import static android.bluetooth.BluetoothAdapter.EXTRA_STATE;
-import static android.bluetooth.BluetoothAdapter.SCAN_MODE_CONNECTABLE;
-import static android.bluetooth.BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE;
-import static android.bluetooth.BluetoothAdapter.SCAN_MODE_NONE;
-import static android.bluetooth.BluetoothAdapter.STATE_OFF;
-import static android.bluetooth.BluetoothAdapter.STATE_ON;
-import static android.bluetooth.BluetoothDevice.EXTRA_DEVICE;
-import static java.util.concurrent.TimeUnit.MILLISECONDS;
-import static java.util.logging.Level.INFO;
-import static java.util.logging.Level.WARNING;
-import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.TRANSPORT_ID_BLUETOOTH;
-import static org.briarproject.bramble.api.plugin.BluetoothConstants.ID;
-import static org.briarproject.bramble.api.plugin.BluetoothConstants.PREF_BT_ENABLE;
-import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_ADDRESS;
-import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_UUID;
-import static org.briarproject.bramble.api.plugin.BluetoothConstants.UUID_BYTES;
-import static org.briarproject.bramble.util.PrivacyUtils.scrubMacAddress;
-
-@MethodsNotNullByDefault
-@ParametersNotNullByDefault
-class DroidtoothPlugin implements DuplexPlugin {
-
-	private static final Logger LOG =
-			Logger.getLogger(DroidtoothPlugin.class.getName());
-	private static final String FOUND =
-			"android.bluetooth.device.action.FOUND";
-	private static final String DISCOVERY_FINISHED =
-			"android.bluetooth.adapter.action.DISCOVERY_FINISHED";
-
-	private final Executor ioExecutor;
-	private final AndroidExecutor androidExecutor;
-	private final Context appContext;
-	private final SecureRandom secureRandom;
-	private final Backoff backoff;
-	private final DuplexPluginCallback callback;
-	private final int maxLatency;
-	private final AtomicBoolean used = new AtomicBoolean(false);
-
-	private volatile boolean running = false;
-	private volatile boolean wasEnabledByUs = false;
-	private volatile BluetoothStateReceiver receiver = null;
-	private volatile BluetoothServerSocket socket = null;
-
-	// Non-null if the plugin started successfully
-	private volatile BluetoothAdapter adapter = null;
-
-	DroidtoothPlugin(Executor ioExecutor, AndroidExecutor androidExecutor,
-			Context appContext, SecureRandom secureRandom, Backoff backoff,
-			DuplexPluginCallback callback, int maxLatency) {
-		this.ioExecutor = ioExecutor;
-		this.androidExecutor = androidExecutor;
-		this.appContext = appContext;
-		this.secureRandom = secureRandom;
-		this.backoff = backoff;
-		this.callback = callback;
-		this.maxLatency = maxLatency;
-	}
-
-	@Override
-	public TransportId getId() {
-		return ID;
-	}
-
-	@Override
-	public int getMaxLatency() {
-		return maxLatency;
-	}
-
-	@Override
-	public int getMaxIdleTime() {
-		// Bluetooth detects dead connections so we don't need keepalives
-		return Integer.MAX_VALUE;
-	}
-
-	@Override
-	public void start() throws PluginException {
-		if (used.getAndSet(true)) throw new IllegalStateException();
-		// BluetoothAdapter.getDefaultAdapter() must be called on a thread
-		// with a message queue, so submit it to the AndroidExecutor
-		try {
-			adapter = androidExecutor.runOnBackgroundThread(
-					new Callable<BluetoothAdapter>() {
-						@Override
-						public BluetoothAdapter call() throws Exception {
-							return BluetoothAdapter.getDefaultAdapter();
-						}
-					}).get();
-		} catch (InterruptedException e) {
-			Thread.currentThread().interrupt();
-			LOG.warning("Interrupted while getting BluetoothAdapter");
-			throw new PluginException(e);
-		} catch (ExecutionException e) {
-			throw new PluginException(e);
-		}
-		if (adapter == null) {
-			LOG.info("Bluetooth is not supported");
-			throw new PluginException();
-		}
-		running = true;
-		// Listen for changes to the Bluetooth state
-		IntentFilter filter = new IntentFilter();
-		filter.addAction(ACTION_STATE_CHANGED);
-		filter.addAction(ACTION_SCAN_MODE_CHANGED);
-		receiver = new BluetoothStateReceiver();
-		appContext.registerReceiver(receiver, filter);
-		// If Bluetooth is enabled, bind a socket
-		if (adapter.isEnabled()) {
-			bind();
-		} else {
-			// Enable Bluetooth if settings allow
-			if (callback.getSettings().getBoolean(PREF_BT_ENABLE, false)) {
-				wasEnabledByUs = true;
-				if (adapter.enable()) LOG.info("Enabling Bluetooth");
-				else LOG.info("Could not enable Bluetooth");
-			} else {
-				LOG.info("Not enabling Bluetooth");
-			}
-		}
-	}
-
-	private void bind() {
-		ioExecutor.execute(new Runnable() {
-			@Override
-			public void run() {
-				if (!isRunning()) return;
-				String address = AndroidUtils.getBluetoothAddress(appContext,
-						adapter);
-				if (LOG.isLoggable(INFO))
-					LOG.info("Local address " + scrubMacAddress(address));
-				if (!StringUtils.isNullOrEmpty(address)) {
-					// Advertise the Bluetooth address to contacts
-					TransportProperties p = new TransportProperties();
-					p.put(PROP_ADDRESS, address);
-					callback.mergeLocalProperties(p);
-				}
-				// Bind a server socket to accept connections from contacts
-				BluetoothServerSocket ss;
-				try {
-					ss = adapter.listenUsingInsecureRfcommWithServiceRecord(
-							"RFCOMM", getUuid());
-				} catch (IOException e) {
-					if (LOG.isLoggable(WARNING))
-						LOG.log(WARNING, e.toString(), e);
-					return;
-				}
-				if (!isRunning()) {
-					tryToClose(ss);
-					return;
-				}
-				LOG.info("Socket bound");
-				socket = ss;
-				backoff.reset();
-				callback.transportEnabled();
-				acceptContactConnections();
-			}
-		});
-	}
-
-	private UUID getUuid() {
-		String uuid = callback.getLocalProperties().get(PROP_UUID);
-		if (uuid == null) {
-			byte[] random = new byte[UUID_BYTES];
-			secureRandom.nextBytes(random);
-			uuid = UUID.nameUUIDFromBytes(random).toString();
-			TransportProperties p = new TransportProperties();
-			p.put(PROP_UUID, uuid);
-			callback.mergeLocalProperties(p);
-		}
-		return UUID.fromString(uuid);
-	}
-
-	private void tryToClose(@Nullable BluetoothServerSocket ss) {
-		try {
-			if (ss != null) ss.close();
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-		} finally {
-			callback.transportDisabled();
-		}
-	}
-
-	private void acceptContactConnections() {
-		while (isRunning()) {
-			BluetoothSocket s;
-			try {
-				s = socket.accept();
-			} catch (IOException e) {
-				// This is expected when the socket is closed
-				if (LOG.isLoggable(INFO)) LOG.info(e.toString());
-				return;
-			}
-			if (LOG.isLoggable(INFO)) {
-				String address = s.getRemoteDevice().getAddress();
-				LOG.info("Connection from " + scrubMacAddress(address));
-			}
-			backoff.reset();
-			callback.incomingConnectionCreated(wrapSocket(s));
-		}
-	}
-
-	private DuplexTransportConnection wrapSocket(BluetoothSocket s) {
-		return new DroidtoothTransportConnection(this, s);
-	}
-
-	@Override
-	public void stop() {
-		running = false;
-		if (receiver != null) appContext.unregisterReceiver(receiver);
-		tryToClose(socket);
-		// Disable Bluetooth if we enabled it and it's still enabled
-		if (wasEnabledByUs && adapter.isEnabled()) {
-			if (adapter.disable()) LOG.info("Disabling Bluetooth");
-			else LOG.info("Could not disable Bluetooth");
-		}
-	}
-
-	@Override
-	public boolean isRunning() {
-		return running && adapter != null && adapter.isEnabled();
-	}
-
-	@Override
-	public boolean shouldPoll() {
-		return true;
-	}
-
-	@Override
-	public int getPollingInterval() {
-		return backoff.getPollingInterval();
-	}
-
-	@Override
-	public void poll(Collection<ContactId> connected) {
-		if (!isRunning()) return;
-		backoff.increment();
-		// Try to connect to known devices in parallel
-		Map<ContactId, TransportProperties> remote =
-				callback.getRemoteProperties();
-		for (Entry<ContactId, TransportProperties> e : remote.entrySet()) {
-			final ContactId c = e.getKey();
-			if (connected.contains(c)) continue;
-			final String address = e.getValue().get(PROP_ADDRESS);
-			if (StringUtils.isNullOrEmpty(address)) continue;
-			final String uuid = e.getValue().get(PROP_UUID);
-			if (StringUtils.isNullOrEmpty(uuid)) continue;
-			ioExecutor.execute(new Runnable() {
-				@Override
-				public void run() {
-					if (!running) return;
-					BluetoothSocket s = connect(address, uuid);
-					if (s != null) {
-						backoff.reset();
-						callback.outgoingConnectionCreated(c, wrapSocket(s));
-					}
-				}
-			});
-		}
-	}
-
-	@Nullable
-	private BluetoothSocket connect(String address, String uuid) {
-		// Validate the address
-		if (!BluetoothAdapter.checkBluetoothAddress(address)) {
-			if (LOG.isLoggable(WARNING))
-				// not scrubbing here to be able to figure out the problem
-				LOG.warning("Invalid address " + address);
-			return null;
-		}
-		// Validate the UUID
-		UUID u;
-		try {
-			u = UUID.fromString(uuid);
-		} catch (IllegalArgumentException e) {
-			if (LOG.isLoggable(WARNING)) LOG.warning("Invalid UUID " + uuid);
-			return null;
-		}
-		// Try to connect
-		BluetoothDevice d = adapter.getRemoteDevice(address);
-		BluetoothSocket s = null;
-		try {
-			s = d.createInsecureRfcommSocketToServiceRecord(u);
-			if (LOG.isLoggable(INFO))
-				LOG.info("Connecting to " + scrubMacAddress(address));
-			s.connect();
-			if (LOG.isLoggable(INFO))
-				LOG.info("Connected to " + scrubMacAddress(address));
-			return s;
-		} catch (IOException e) {
-			if (LOG.isLoggable(INFO)) {
-				LOG.info("Failed to connect to " + scrubMacAddress(address)
-						+ ": " + e);
-			}
-			tryToClose(s);
-			return null;
-		}
-	}
-
-	private void tryToClose(@Nullable Closeable c) {
-		try {
-			if (c != null) c.close();
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-		}
-	}
-
-	@Override
-	public DuplexTransportConnection createConnection(ContactId c) {
-		if (!isRunning()) return null;
-		TransportProperties p = callback.getRemoteProperties().get(c);
-		if (p == null) return null;
-		String address = p.get(PROP_ADDRESS);
-		if (StringUtils.isNullOrEmpty(address)) return null;
-		String uuid = p.get(PROP_UUID);
-		if (StringUtils.isNullOrEmpty(uuid)) return null;
-		BluetoothSocket s = connect(address, uuid);
-		if (s == null) return null;
-		return new DroidtoothTransportConnection(this, s);
-	}
-
-	@Override
-	public boolean supportsInvitations() {
-		return true;
-	}
-
-	@Override
-	public DuplexTransportConnection createInvitationConnection(PseudoRandom r,
-			long timeout, boolean alice) {
-		if (!isRunning()) return null;
-		// Use the invitation codes to generate the UUID
-		byte[] b = r.nextBytes(UUID_BYTES);
-		UUID uuid = UUID.nameUUIDFromBytes(b);
-		if (LOG.isLoggable(INFO)) LOG.info("Invitation UUID " + uuid);
-		// Bind a server socket for receiving invitation connections
-		BluetoothServerSocket ss;
-		try {
-			ss = adapter.listenUsingInsecureRfcommWithServiceRecord(
-					"RFCOMM", uuid);
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			return null;
-		}
-		// Create the background tasks
-		CompletionService<BluetoothSocket> complete =
-				new ExecutorCompletionService<>(ioExecutor);
-		List<Future<BluetoothSocket>> futures = new ArrayList<>();
-		if (alice) {
-			// Return the first connected socket
-			futures.add(complete.submit(new ListeningTask(ss)));
-			futures.add(complete.submit(new DiscoveryTask(uuid.toString())));
-		} else {
-			// Return the first socket with readable data
-			futures.add(complete.submit(new ReadableTask(
-					new ListeningTask(ss))));
-			futures.add(complete.submit(new ReadableTask(
-					new DiscoveryTask(uuid.toString()))));
-		}
-		BluetoothSocket chosen = null;
-		try {
-			Future<BluetoothSocket> f = complete.poll(timeout, MILLISECONDS);
-			if (f == null) return null; // No task completed within the timeout
-			chosen = f.get();
-			return new DroidtoothTransportConnection(this, chosen);
-		} catch (InterruptedException e) {
-			LOG.info("Interrupted while exchanging invitations");
-			Thread.currentThread().interrupt();
-			return null;
-		} catch (ExecutionException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			return null;
-		} finally {
-			// Closing the socket will terminate the listener task
-			tryToClose(ss);
-			closeSockets(futures, chosen);
-		}
-	}
-
-	private void closeSockets(final List<Future<BluetoothSocket>> futures,
-			@Nullable final BluetoothSocket chosen) {
-		ioExecutor.execute(new Runnable() {
-			@Override
-			public void run() {
-				for (Future<BluetoothSocket> f : futures) {
-					try {
-						if (f.cancel(true)) {
-							LOG.info("Cancelled task");
-						} else {
-							BluetoothSocket s = f.get();
-							if (s != null && s != chosen) {
-								LOG.info("Closing unwanted socket");
-								s.close();
-							}
-						}
-					} catch (InterruptedException e) {
-						LOG.info("Interrupted while closing sockets");
-						return;
-					} catch (ExecutionException | IOException e) {
-						if (LOG.isLoggable(INFO)) LOG.info(e.toString());
-					}
-				}
-			}
-		});
-	}
-
-	@Override
-	public boolean supportsKeyAgreement() {
-		return true;
-	}
-
-	@Override
-	public KeyAgreementListener createKeyAgreementListener(byte[] commitment) {
-		if (!isRunning()) return null;
-		// There's no point listening if we can't discover our own address
-		String address = AndroidUtils.getBluetoothAddress(appContext, adapter);
-		if (address.isEmpty()) return null;
-		// No truncation necessary because COMMIT_LENGTH = 16
-		UUID uuid = UUID.nameUUIDFromBytes(commitment);
-		if (LOG.isLoggable(INFO)) LOG.info("Key agreement UUID " + uuid);
-		// Bind a server socket for receiving invitation connections
-		BluetoothServerSocket ss;
-		try {
-			ss = adapter.listenUsingInsecureRfcommWithServiceRecord(
-					"RFCOMM", uuid);
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			return null;
-		}
-		BdfList descriptor = new BdfList();
-		descriptor.add(TRANSPORT_ID_BLUETOOTH);
-		descriptor.add(StringUtils.macToBytes(address));
-		return new BluetoothKeyAgreementListener(descriptor, ss);
-	}
-
-	@Override
-	public DuplexTransportConnection createKeyAgreementConnection(
-			byte[] commitment, BdfList descriptor, long timeout) {
-		if (!isRunning()) return null;
-		String address;
-		try {
-			address = parseAddress(descriptor);
-		} catch (FormatException e) {
-			LOG.info("Invalid address in key agreement descriptor");
-			return null;
-		}
-		// No truncation necessary because COMMIT_LENGTH = 16
-		UUID uuid = UUID.nameUUIDFromBytes(commitment);
-		if (LOG.isLoggable(INFO))
-			LOG.info("Connecting to key agreement UUID " + uuid);
-		BluetoothSocket s = connect(address, uuid.toString());
-		if (s == null) return null;
-		return new DroidtoothTransportConnection(this, s);
-	}
-
-	private String parseAddress(BdfList descriptor) throws FormatException {
-		byte[] mac = descriptor.getRaw(1);
-		if (mac.length != 6) throw new FormatException();
-		return StringUtils.macToString(mac);
-	}
-
-	private class BluetoothStateReceiver extends BroadcastReceiver {
-
-		@Override
-		public void onReceive(Context ctx, Intent intent) {
-			int state = intent.getIntExtra(EXTRA_STATE, 0);
-			if (state == STATE_ON) {
-				LOG.info("Bluetooth enabled");
-				bind();
-			} else if (state == STATE_OFF) {
-				LOG.info("Bluetooth disabled");
-				tryToClose(socket);
-			}
-			int scanMode = intent.getIntExtra(EXTRA_SCAN_MODE, 0);
-			if (scanMode == SCAN_MODE_NONE) {
-				LOG.info("Scan mode: None");
-			} else if (scanMode == SCAN_MODE_CONNECTABLE) {
-				LOG.info("Scan mode: Connectable");
-			} else if (scanMode == SCAN_MODE_CONNECTABLE_DISCOVERABLE) {
-				LOG.info("Scan mode: Discoverable");
-			}
-		}
-	}
-
-	private class DiscoveryTask implements Callable<BluetoothSocket> {
-
-		private final String uuid;
-
-		private DiscoveryTask(String uuid) {
-			this.uuid = uuid;
-		}
-
-		@Override
-		public BluetoothSocket call() throws Exception {
-			// Repeat discovery until we connect or get interrupted
-			while (true) {
-				// Discover nearby devices
-				LOG.info("Discovering nearby devices");
-				List<String> addresses = discoverDevices();
-				if (addresses.isEmpty()) {
-					LOG.info("No devices discovered");
-					continue;
-				}
-				// Connect to any device with the right UUID
-				for (String address : addresses) {
-					BluetoothSocket s = connect(address, uuid);
-					if (s != null) {
-						LOG.info("Outgoing connection");
-						return s;
-					}
-				}
-			}
-		}
-
-		private List<String> discoverDevices() throws InterruptedException {
-			IntentFilter filter = new IntentFilter();
-			filter.addAction(FOUND);
-			filter.addAction(DISCOVERY_FINISHED);
-			DiscoveryReceiver disco = new DiscoveryReceiver();
-			appContext.registerReceiver(disco, filter);
-			LOG.info("Starting discovery");
-			adapter.startDiscovery();
-			return disco.waitForAddresses();
-		}
-	}
-
-	private static class DiscoveryReceiver extends BroadcastReceiver {
-
-		private final CountDownLatch finished = new CountDownLatch(1);
-		private final List<String> addresses = new CopyOnWriteArrayList<>();
-
-		@Override
-		public void onReceive(Context ctx, Intent intent) {
-			String action = intent.getAction();
-			if (action.equals(DISCOVERY_FINISHED)) {
-				LOG.info("Discovery finished");
-				ctx.unregisterReceiver(this);
-				finished.countDown();
-			} else if (action.equals(FOUND)) {
-				BluetoothDevice d = intent.getParcelableExtra(EXTRA_DEVICE);
-				if (LOG.isLoggable(INFO)) {
-					LOG.info("Discovered device: " +
-							scrubMacAddress(d.getAddress()));
-				}
-				addresses.add(d.getAddress());
-			}
-		}
-
-		private List<String> waitForAddresses() throws InterruptedException {
-			finished.await();
-			List<String> shuffled = new ArrayList<>(addresses);
-			Collections.shuffle(shuffled);
-			return shuffled;
-		}
-	}
-
-	private static class ListeningTask implements Callable<BluetoothSocket> {
-
-		private final BluetoothServerSocket serverSocket;
-
-		private ListeningTask(BluetoothServerSocket serverSocket) {
-			this.serverSocket = serverSocket;
-		}
-
-		@Override
-		public BluetoothSocket call() throws IOException {
-			BluetoothSocket s = serverSocket.accept();
-			LOG.info("Incoming connection");
-			return s;
-		}
-	}
-
-	private static class ReadableTask implements Callable<BluetoothSocket> {
-
-		private final Callable<BluetoothSocket> connectionTask;
-
-		private ReadableTask(Callable<BluetoothSocket> connectionTask) {
-			this.connectionTask = connectionTask;
-		}
-
-		@Override
-		public BluetoothSocket call() throws Exception {
-			BluetoothSocket s = connectionTask.call();
-			InputStream in = s.getInputStream();
-			while (in.available() == 0) {
-				LOG.info("Waiting for data");
-				Thread.sleep(1000);
-			}
-			LOG.info("Data available");
-			return s;
-		}
-	}
-
-	private class BluetoothKeyAgreementListener extends KeyAgreementListener {
-
-		private final BluetoothServerSocket ss;
-
-		private BluetoothKeyAgreementListener(BdfList descriptor,
-				BluetoothServerSocket ss) {
-			super(descriptor);
-			this.ss = ss;
-		}
-
-		@Override
-		public Callable<KeyAgreementConnection> listen() {
-			return new Callable<KeyAgreementConnection>() {
-				@Override
-				public KeyAgreementConnection call() throws IOException {
-					BluetoothSocket s = ss.accept();
-					if (LOG.isLoggable(INFO))
-						LOG.info(ID.getString() + ": Incoming connection");
-					return new KeyAgreementConnection(
-							new DroidtoothTransportConnection(
-									DroidtoothPlugin.this, s), ID);
-				}
-			};
-		}
-
-		@Override
-		public void close() {
-			try {
-				ss.close();
-			} catch (IOException e) {
-				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			}
-		}
-	}
-}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/droidtooth/DroidtoothPluginFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/droidtooth/DroidtoothPluginFactory.java
@@ -1,63 +0,0 @@
-package org.briarproject.bramble.plugin.droidtooth;
-
-import android.content.Context;
-
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.plugin.Backoff;
-import org.briarproject.bramble.api.plugin.BackoffFactory;
-import org.briarproject.bramble.api.plugin.TransportId;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
-import org.briarproject.bramble.api.system.AndroidExecutor;
-
-import java.security.SecureRandom;
-import java.util.concurrent.Executor;
-
-import javax.annotation.concurrent.Immutable;
-
-import static org.briarproject.bramble.api.plugin.BluetoothConstants.ID;
-
-@Immutable
-@NotNullByDefault
-public class DroidtoothPluginFactory implements DuplexPluginFactory {
-
-	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
-	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
-	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
-	private static final double BACKOFF_BASE = 1.2;
-
-	private final Executor ioExecutor;
-	private final AndroidExecutor androidExecutor;
-	private final Context appContext;
-	private final SecureRandom secureRandom;
-	private final BackoffFactory backoffFactory;
-
-	public DroidtoothPluginFactory(Executor ioExecutor,
-			AndroidExecutor androidExecutor, Context appContext,
-			SecureRandom secureRandom, BackoffFactory backoffFactory) {
-		this.ioExecutor = ioExecutor;
-		this.androidExecutor = androidExecutor;
-		this.appContext = appContext;
-		this.secureRandom = secureRandom;
-		this.backoffFactory = backoffFactory;
-	}
-
-	@Override
-	public TransportId getId() {
-		return ID;
-	}
-
-	@Override
-	public int getMaxLatency() {
-		return MAX_LATENCY;
-	}
-
-	@Override
-	public DuplexPlugin createPlugin(DuplexPluginCallback callback) {
-		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
-				MAX_POLLING_INTERVAL, BACKOFF_BASE);
-		return new DroidtoothPlugin(ioExecutor, androidExecutor, appContext,
-				secureRandom, backoff, callback, MAX_LATENCY);
-	}
-}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/droidtooth/DroidtoothTransportConnection.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/droidtooth/DroidtoothTransportConnection.java
@@ -1,37 +0,0 @@
-package org.briarproject.bramble.plugin.droidtooth;
-
-import android.bluetooth.BluetoothSocket;
-
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.plugin.Plugin;
-import org.briarproject.bramble.api.plugin.duplex.AbstractDuplexTransportConnection;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-
-@NotNullByDefault
-class DroidtoothTransportConnection extends AbstractDuplexTransportConnection {
-
-	private final BluetoothSocket socket;
-
-	DroidtoothTransportConnection(Plugin plugin, BluetoothSocket socket) {
-		super(plugin);
-		this.socket = socket;
-	}
-
-	@Override
-	protected InputStream getInputStream() throws IOException {
-		return socket.getInputStream();
-	}
-
-	@Override
-	protected OutputStream getOutputStream() throws IOException {
-		return socket.getOutputStream();
-	}
-
-	@Override
-	protected void closeConnection(boolean exception) throws IOException {
-		socket.close();
-	}
-}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tcp/AndroidLanTcpPlugin.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tcp/AndroidLanTcpPlugin.java
@@ -1,76 +1,307 @@
 package org.briarproject.bramble.plugin.tcp;

-import android.content.BroadcastReceiver;
-import android.content.Context;
-import android.content.Intent;
-import android.content.IntentFilter;
+import android.annotation.TargetApi;
+import android.app.Application;
 import android.net.ConnectivityManager;
-import android.net.NetworkInfo;
+import android.net.LinkAddress;
+import android.net.LinkProperties;
+import android.net.Network;
+import android.net.NetworkCapabilities;
+import android.net.wifi.WifiInfo;
+import android.net.wifi.WifiManager;

+import org.briarproject.bramble.PoliteExecutor;
+import org.briarproject.bramble.api.Pair;
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.network.event.NetworkStatusEvent;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Backoff;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
+import org.briarproject.bramble.api.plugin.PluginCallback;
+import org.briarproject.bramble.api.settings.Settings;

+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.InterfaceAddress;
+import java.net.NetworkInterface;
+import java.net.Socket;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+import java.util.List;
 import java.util.concurrent.Executor;
 import java.util.logging.Logger;

 import javax.annotation.Nullable;
+import javax.net.SocketFactory;

 import static android.content.Context.CONNECTIVITY_SERVICE;
-import static android.net.ConnectivityManager.CONNECTIVITY_ACTION;
-import static android.net.ConnectivityManager.TYPE_WIFI;
+import static android.content.Context.WIFI_SERVICE;
+import static android.net.NetworkCapabilities.TRANSPORT_WIFI;
+import static android.os.Build.VERSION.SDK_INT;
+import static java.util.Collections.emptyList;
+import static java.util.Collections.list;
+import static java.util.Collections.singletonList;
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+import static org.briarproject.bramble.api.plugin.LanTcpConstants.DEFAULT_PREF_PLUGIN_ENABLE;
+import static org.briarproject.bramble.api.plugin.Plugin.State.ACTIVE;
+import static org.briarproject.bramble.api.plugin.Plugin.State.INACTIVE;
+import static org.briarproject.bramble.util.IoUtils.tryToClose;
+import static org.briarproject.bramble.util.LogUtils.logException;

@NotNullByDefault
 class AndroidLanTcpPlugin extends LanTcpPlugin {

 	private static final Logger LOG =
-			Logger.getLogger(AndroidLanTcpPlugin.class.getName());
-
-	private final Context appContext;
+			getLogger(AndroidLanTcpPlugin.class.getName());

+	private final Executor connectionStatusExecutor;
+	private final ConnectivityManager connectivityManager;
 	@Nullable
-	private volatile BroadcastReceiver networkStateReceiver = null;
+	private final WifiManager wifiManager;

-	AndroidLanTcpPlugin(Executor ioExecutor, Backoff backoff,
-			Context appContext, DuplexPluginCallback callback, int maxLatency,
-			int maxIdleTime) {
-		super(ioExecutor, backoff, callback, maxLatency, maxIdleTime);
-		this.appContext = appContext;
+	private volatile SocketFactory socketFactory;
+
+	AndroidLanTcpPlugin(Executor ioExecutor,
+			Executor wakefulIoExecutor,
+			Application app,
+			Backoff backoff,
+			PluginCallback callback,
+			int maxLatency,
+			int maxIdleTime,
+			int connectionTimeout) {
+		super(ioExecutor, wakefulIoExecutor, backoff, callback, maxLatency,
+				maxIdleTime, connectionTimeout);
+		// Don't execute more than one connection status check at a time
+		connectionStatusExecutor =
+				new PoliteExecutor("AndroidLanTcpPlugin", ioExecutor, 1);
+		connectivityManager = (ConnectivityManager)
+				requireNonNull(app.getSystemService(CONNECTIVITY_SERVICE));
+		wifiManager = (WifiManager) app.getSystemService(WIFI_SERVICE);
+		socketFactory = SocketFactory.getDefault();
 	}

 	@Override
 	public void start() {
 		if (used.getAndSet(true)) throw new IllegalStateException();
-		running = true;
-		// Register to receive network status events
-		networkStateReceiver = new NetworkStateReceiver();
-		IntentFilter filter = new IntentFilter(CONNECTIVITY_ACTION);
-		appContext.registerReceiver(networkStateReceiver, filter);
+		initialisePortProperty();
+		Settings settings = callback.getSettings();
+		state.setStarted(settings.getBoolean(PREF_PLUGIN_ENABLE,
+				DEFAULT_PREF_PLUGIN_ENABLE));
+		updateConnectionStatus();
 	}

 	@Override
-	public void stop() {
-		running = false;
-		if (networkStateReceiver != null)
-			appContext.unregisterReceiver(networkStateReceiver);
-		tryToClose(socket);
+	protected Socket createSocket() throws IOException {
+		return socketFactory.createSocket();
 	}

-	private class NetworkStateReceiver extends BroadcastReceiver {
+	@Override
+	protected List<InetAddress> getUsableLocalInetAddresses(boolean ipv4) {
+		InetAddress addr = getWifiAddress(ipv4);
+		return addr == null ? emptyList() : singletonList(addr);
+	}

-		@Override
-		public void onReceive(Context ctx, Intent i) {
-			if (!running) return;
-			Object o = ctx.getSystemService(CONNECTIVITY_SERVICE);
-			ConnectivityManager cm = (ConnectivityManager) o;
-			NetworkInfo net = cm.getActiveNetworkInfo();
-			if (net != null && net.getType() == TYPE_WIFI && net.isConnected()) {
-				LOG.info("Connected to Wi-Fi");
-				if (socket == null || socket.isClosed()) bind();
-			} else {
-				LOG.info("Not connected to Wi-Fi");
-				tryToClose(socket);
+	@Nullable
+	private InetAddress getWifiAddress(boolean ipv4) {
+		Pair<InetAddress, Boolean> wifi = getWifiIpv4Address();
+		if (ipv4) return wifi == null ? null : wifi.getFirst();
+		// If there's no wifi IPv4 address, we might be a client on an
+		// IPv6-only wifi network. We can only detect this on API 21+
+		if (wifi == null) {
+			return SDK_INT >= 21 ? getWifiClientIpv6Address() : null;
+		}
+		// Use the wifi IPv4 address to determine which interface's IPv6
+		// address we should return (if the interface has a suitable address)
+		return getIpv6AddressForInterface(wifi.getFirst());
+	}
+
+	/**
+	 * Returns a {@link Pair} where the first element is the IPv4 address of
+	 * the wifi interface and the second element is true if this device is
+	 * providing an access point, or false if this device is a client. Returns
+	 * null if this device isn't connected to wifi as an access point or client.
+	 */
+	@Nullable
+	private Pair<InetAddress, Boolean> getWifiIpv4Address() {
+		if (wifiManager == null) return null;
+		// If we're connected to a wifi network, return its address
+		WifiInfo info = wifiManager.getConnectionInfo();
+		if (info != null && info.getIpAddress() != 0) {
+			return new Pair<>(intToInetAddress(info.getIpAddress()), false);
+		}
+		List<InterfaceAddress> ifAddrs = getLocalInterfaceAddresses();
+		// If we're providing a normal access point, return its address
+		for (InterfaceAddress ifAddr : ifAddrs) {
+			if (isAndroidWifiApAddress(ifAddr)) {
+				return new Pair<>(ifAddr.getAddress(), true);
 			}
 		}
+		// If we're providing a wifi direct access point, return its address
+		for (InterfaceAddress ifAddr : ifAddrs) {
+			if (isAndroidWifiDirectApAddress(ifAddr)) {
+				return new Pair<>(ifAddr.getAddress(), true);
+			}
+		}
+		// Not connected to wifi
+		return null;
 	}
-}
+
+	/**
+	 * Returns true if the given address belongs to a network provided by an
+	 * Android access point (including the access point's own address).
+	 * <p>
+	 * The access point's address is usually 192.168.43.1, but at least one
+	 * device (Honor 8A) may use other addresses in the range 192.168.43.0/24.
+	 */
+	private boolean isAndroidWifiApAddress(InterfaceAddress ifAddr) {
+		if (ifAddr.getNetworkPrefixLength() != 24) return false;
+		byte[] ip = ifAddr.getAddress().getAddress();
+		return ip.length == 4
+				&& ip[0] == (byte) 192
+				&& ip[1] == (byte) 168
+				&& ip[2] == (byte) 43;
+	}
+
+	/**
+	 * Returns true if the given address belongs to a network provided by an
+	 * Android wifi direct legacy mode access point (including the access
+	 * point's own address).
+	 */
+	private boolean isAndroidWifiDirectApAddress(InterfaceAddress ifAddr) {
+		if (ifAddr.getNetworkPrefixLength() != 24) return false;
+		byte[] ip = ifAddr.getAddress().getAddress();
+		return ip.length == 4
+				&& ip[0] == (byte) 192
+				&& ip[1] == (byte) 168
+				&& ip[2] == (byte) 49;
+	}
+
+	/**
+	 * Returns a link-local IPv6 address for the wifi client interface, or null
+	 * if there's no such interface or it doesn't have a suitable address.
+	 */
+	@TargetApi(21)
+	@Nullable
+	private InetAddress getWifiClientIpv6Address() {
+		for (Network net : connectivityManager.getAllNetworks()) {
+			NetworkCapabilities caps =
+					connectivityManager.getNetworkCapabilities(net);
+			if (caps == null || !caps.hasTransport(TRANSPORT_WIFI)) continue;
+			LinkProperties props = connectivityManager.getLinkProperties(net);
+			if (props == null) continue;
+			for (LinkAddress linkAddress : props.getLinkAddresses()) {
+				InetAddress addr = linkAddress.getAddress();
+				if (isIpv6LinkLocalAddress(addr)) return addr;
+			}
+		}
+		return null;
+	}
+
+	/**
+	 * Returns a link-local IPv6 address for the interface with the given IPv4
+	 * address, or null if the interface doesn't have a suitable address.
+	 */
+	@Nullable
+	private InetAddress getIpv6AddressForInterface(InetAddress ipv4) {
+		try {
+			NetworkInterface iface = NetworkInterface.getByInetAddress(ipv4);
+			if (iface == null) return null;
+			for (InetAddress addr : list(iface.getInetAddresses())) {
+				if (isIpv6LinkLocalAddress(addr)) return addr;
+			}
+			// No suitable address
+			return null;
+		} catch (SocketException e) {
+			logException(LOG, WARNING, e);
+			return null;
+		}
+	}
+
+	private InetAddress intToInetAddress(int ip) {
+		byte[] ipBytes = new byte[4];
+		ipBytes[0] = (byte) (ip & 0xFF);
+		ipBytes[1] = (byte) ((ip >> 8) & 0xFF);
+		ipBytes[2] = (byte) ((ip >> 16) & 0xFF);
+		ipBytes[3] = (byte) ((ip >> 24) & 0xFF);
+		try {
+			return InetAddress.getByAddress(ipBytes);
+		} catch (UnknownHostException e) {
+			// Should only be thrown if address has illegal length
+			throw new AssertionError(e);
+		}
+	}
+
+	// On API 21 and later, a socket that is not created with the wifi
+	// network's socket factory may try to connect via another network
+	private SocketFactory getSocketFactory() {
+		if (SDK_INT < 21) return SocketFactory.getDefault();
+		for (Network net : connectivityManager.getAllNetworks()) {
+			NetworkCapabilities caps =
+					connectivityManager.getNetworkCapabilities(net);
+			if (caps != null && caps.hasTransport(TRANSPORT_WIFI)) {
+				return net.getSocketFactory();
+			}
+		}
+		LOG.warning("Could not find suitable socket factory");
+		return SocketFactory.getDefault();
+	}
+
+	@Override
+	public void eventOccurred(Event e) {
+		super.eventOccurred(e);
+		if (e instanceof NetworkStatusEvent) updateConnectionStatus();
+	}
+
+	private void updateConnectionStatus() {
+		connectionStatusExecutor.execute(() -> {
+			State s = getState();
+			if (s != ACTIVE && s != INACTIVE) return;
+			Pair<InetAddress, Boolean> wifi = getPreferredWifiAddress();
+			if (wifi == null) {
+				LOG.info("Not connected to wifi");
+				socketFactory = SocketFactory.getDefault();
+				// Server sockets may not have been closed automatically when
+				// interface was taken down. If any sockets are open, closing
+				// them here will cause the sockets to be cleared and the state
+				// to be updated in acceptContactConnections()
+				if (s == ACTIVE) {
+					LOG.info("Closing server sockets");
+					tryToClose(state.getServerSocket(true), LOG, WARNING);
+					tryToClose(state.getServerSocket(false), LOG, WARNING);
+				}
+			} else if (wifi.getSecond()) {
+				LOG.info("Providing wifi hotspot");
+				// There's no corresponding Network object and thus no way
+				// to get a suitable socket factory, so we won't be able to
+				// make outgoing connections on API 21+ if another network
+				// has internet access
+				socketFactory = SocketFactory.getDefault();
+				bind();
+			} else {
+				LOG.info("Connected to wifi");
+				socketFactory = getSocketFactory();
+				bind();
+			}
+		});
+	}
+
+	/**
+	 * Returns a {@link Pair} where the first element is an IP address (IPv4 if
+	 * available, otherwise IPv6) of the wifi interface and the second element
+	 * is true if this device is providing an access point, or false if this
+	 * device is a client. Returns null if this device isn't connected to wifi
+	 * as an access point or client.
+	 */
+	@Nullable
+	private Pair<InetAddress, Boolean> getPreferredWifiAddress() {
+		Pair<InetAddress, Boolean> wifi = getWifiIpv4Address();
+		// If there's no wifi IPv4 address, we might be a client on an
+		// IPv6-only wifi network. We can only detect this on API 21+
+		if (wifi == null && SDK_INT >= 21) {
+			InetAddress ipv6 = getWifiClientIpv6Address();
+			if (ipv6 != null) return new Pair<>(ipv6, false);
+		}
+		return wifi;
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tcp/AndroidLanTcpPluginFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tcp/AndroidLanTcpPluginFactory.java
@@ -1,18 +1,22 @@
 package org.briarproject.bramble.plugin.tcp;

-import android.content.Context;
+import android.app.Application;

+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Backoff;
 import org.briarproject.bramble.api.plugin.BackoffFactory;
+import org.briarproject.bramble.api.plugin.PluginCallback;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
+import org.briarproject.bramble.api.system.WakefulIoExecutor;

 import java.util.concurrent.Executor;

 import javax.annotation.concurrent.Immutable;
+import javax.inject.Inject;

 import static org.briarproject.bramble.api.plugin.LanTcpConstants.ID;

@@ -20,21 +24,29 @@ import static org.briarproject.bramble.api.plugin.LanTcpConstants.ID;
@NotNullByDefault
 public class AndroidLanTcpPluginFactory implements DuplexPluginFactory {

-	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
-	private static final int MAX_IDLE_TIME = 30 * 1000; // 30 seconds
-	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
-	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
+	private static final int MAX_LATENCY = 30_000; // 30 seconds
+	private static final int MAX_IDLE_TIME = 30_000; // 30 seconds
+	private static final int CONNECTION_TIMEOUT = 3_000; // 3 seconds
+	private static final int MIN_POLLING_INTERVAL = 60_000; // 1 minute
+	private static final int MAX_POLLING_INTERVAL = 600_000; // 10 mins
 	private static final double BACKOFF_BASE = 1.2;

-	private final Executor ioExecutor;
+	private final Executor ioExecutor, wakefulIoExecutor;
+	private final EventBus eventBus;
 	private final BackoffFactory backoffFactory;
-	private final Context appContext;
+	private final Application app;

-	public AndroidLanTcpPluginFactory(Executor ioExecutor,
-			BackoffFactory backoffFactory, Context appContext) {
+	@Inject
+	public AndroidLanTcpPluginFactory(@IoExecutor Executor ioExecutor,
+			@WakefulIoExecutor Executor wakefulIoExecutor,
+			EventBus eventBus,
+			BackoffFactory backoffFactory,
+			Application app) {
 		this.ioExecutor = ioExecutor;
+		this.wakefulIoExecutor = wakefulIoExecutor;
+		this.eventBus = eventBus;
 		this.backoffFactory = backoffFactory;
-		this.appContext = appContext;
+		this.app = app;
 	}

 	@Override
@@ -48,10 +60,13 @@ public class AndroidLanTcpPluginFactory implements DuplexPluginFactory {
 	}

 	@Override
-	public DuplexPlugin createPlugin(DuplexPluginCallback callback) {
+	public DuplexPlugin createPlugin(PluginCallback callback) {
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
-		return new AndroidLanTcpPlugin(ioExecutor, backoff, appContext,
-				callback, MAX_LATENCY, MAX_IDLE_TIME);
+		AndroidLanTcpPlugin plugin = new AndroidLanTcpPlugin(ioExecutor,
+				wakefulIoExecutor, app, backoff, callback,
+				MAX_LATENCY, MAX_IDLE_TIME, CONNECTION_TIMEOUT);
+		eventBus.addListener(plugin);
+		return plugin;
 	}
 }
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/AndroidTorPlugin.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/AndroidTorPlugin.java
@@ -0,0 +1,222 @@
+package org.briarproject.bramble.plugin.tor;
+
+import android.app.Application;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
+
+import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.network.NetworkManager;
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
+import org.briarproject.bramble.api.plugin.Backoff;
+import org.briarproject.bramble.api.plugin.PluginCallback;
+import org.briarproject.bramble.api.system.AndroidWakeLock;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.bramble.api.system.LocationUtils;
+import org.briarproject.bramble.api.system.ResourceProvider;
+import org.briarproject.bramble.util.AndroidUtils;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.Executor;
+import java.util.logging.Logger;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
+
+import javax.net.SocketFactory;
+
+import static android.os.Build.VERSION.SDK_INT;
+import static java.util.Arrays.asList;
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Logger.getLogger;
+
+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
+class AndroidTorPlugin extends TorPlugin {
+
+	private static final List<String> LIBRARY_ARCHITECTURES =
+			asList("armeabi-v7a", "arm64-v8a", "x86", "x86_64");
+
+	private static final String TOR_LIB_NAME = "libtor.so";
+	private static final String OBFS4_LIB_NAME = "libobfs4proxy.so";
+
+	private static final Logger LOG =
+			getLogger(AndroidTorPlugin.class.getName());
+
+	private final Application app;
+	private final AndroidWakeLock wakeLock;
+	private final File torLib, obfs4Lib;
+
+	AndroidTorPlugin(Executor ioExecutor,
+			Executor wakefulIoExecutor,
+			Application app,
+			NetworkManager networkManager,
+			LocationUtils locationUtils,
+			SocketFactory torSocketFactory,
+			Clock clock,
+			ResourceProvider resourceProvider,
+			CircumventionProvider circumventionProvider,
+			BatteryManager batteryManager,
+			AndroidWakeLockManager wakeLockManager,
+			Backoff backoff,
+			TorRendezvousCrypto torRendezvousCrypto,
+			PluginCallback callback,
+			String architecture,
+			int maxLatency,
+			int maxIdleTime,
+			File torDirectory) {
+		super(ioExecutor, wakefulIoExecutor, networkManager, locationUtils,
+				torSocketFactory, clock, resourceProvider,
+				circumventionProvider, batteryManager, backoff,
+				torRendezvousCrypto, callback, architecture, maxLatency,
+				maxIdleTime, torDirectory);
+		this.app = app;
+		wakeLock = wakeLockManager.createWakeLock("TorPlugin");
+		String nativeLibDir = app.getApplicationInfo().nativeLibraryDir;
+		torLib = new File(nativeLibDir, TOR_LIB_NAME);
+		obfs4Lib = new File(nativeLibDir, OBFS4_LIB_NAME);
+	}
+
+	@Override
+	protected int getProcessId() {
+		return android.os.Process.myPid();
+	}
+
+	@Override
+	protected long getLastUpdateTime() {
+		try {
+			PackageManager pm = app.getPackageManager();
+			PackageInfo pi = pm.getPackageInfo(app.getPackageName(), 0);
+			return pi.lastUpdateTime;
+		} catch (NameNotFoundException e) {
+			throw new AssertionError(e);
+		}
+	}
+
+	@Override
+	protected void enableNetwork(boolean enable) throws IOException {
+		if (enable) wakeLock.acquire();
+		super.enableNetwork(enable);
+		if (!enable) wakeLock.release();
+	}
+
+	@Override
+	public void stop() {
+		super.stop();
+		wakeLock.release();
+	}
+
+	@Override
+	protected File getTorExecutableFile() {
+		return torLib.exists() ? torLib : super.getTorExecutableFile();
+	}
+
+	@Override
+	protected File getObfs4ExecutableFile() {
+		return obfs4Lib.exists() ? obfs4Lib : super.getObfs4ExecutableFile();
+	}
+
+	@Override
+	protected void installTorExecutable() throws IOException {
+		File extracted = super.getTorExecutableFile();
+		if (torLib.exists()) {
+			// If an older version left behind a Tor binary, delete it
+			if (extracted.exists()) {
+				if (extracted.delete()) LOG.info("Deleted Tor binary");
+				else LOG.info("Failed to delete Tor binary");
+			}
+		} else if (SDK_INT < 29) {
+			// The binary wasn't extracted at install time. Try to extract it
+			extractLibraryFromApk(TOR_LIB_NAME, extracted);
+		} else {
+			// No point extracting the binary, we won't be allowed to execute it
+			throw new FileNotFoundException(torLib.getAbsolutePath());
+		}
+	}
+
+	@Override
+	protected void installObfs4Executable() throws IOException {
+		File extracted = super.getObfs4ExecutableFile();
+		if (obfs4Lib.exists()) {
+			// If an older version left behind an obfs4 binary, delete it
+			if (extracted.exists()) {
+				if (extracted.delete()) LOG.info("Deleted obfs4 binary");
+				else LOG.info("Failed to delete obfs4 binary");
+			}
+		} else if (SDK_INT < 29) {
+			// The binary wasn't extracted at install time. Try to extract it
+			extractLibraryFromApk(OBFS4_LIB_NAME, extracted);
+		} else {
+			// No point extracting the binary, we won't be allowed to execute it
+			throw new FileNotFoundException(obfs4Lib.getAbsolutePath());
+		}
+	}
+
+	private void extractLibraryFromApk(String libName, File dest)
+			throws IOException {
+		File sourceDir = new File(app.getApplicationInfo().sourceDir);
+		if (sourceDir.isFile()) {
+			// Look for other APK files in the same directory, if we're allowed
+			File parent = sourceDir.getParentFile();
+			if (parent != null) sourceDir = parent;
+		}
+		List<String> libPaths = getSupportedLibraryPaths(libName);
+		for (File apk : findApkFiles(sourceDir)) {
+			ZipInputStream zin = new ZipInputStream(new FileInputStream(apk));
+			for (ZipEntry e = zin.getNextEntry(); e != null;
+					e = zin.getNextEntry()) {
+				if (libPaths.contains(e.getName())) {
+					if (LOG.isLoggable(INFO)) {
+						LOG.info("Extracting " + e.getName()
+								+ " from " + apk.getAbsolutePath());
+					}
+					extract(zin, dest); // Zip input stream will be closed
+					return;
+				}
+			}
+			zin.close();
+		}
+		throw new FileNotFoundException(libName);
+	}
+
+	/**
+	 * Returns all files with the extension .apk or .APK under the given root.
+	 */
+	private List<File> findApkFiles(File root) {
+		List<File> files = new ArrayList<>();
+		findApkFiles(root, files);
+		return files;
+	}
+
+	private void findApkFiles(File f, List<File> files) {
+		if (f.isFile() && f.getName().toLowerCase().endsWith(".apk")) {
+			files.add(f);
+		} else if (f.isDirectory()) {
+			File[] children = f.listFiles();
+			if (children != null) {
+				for (File child : children) findApkFiles(child, files);
+			}
+		}
+	}
+
+	/**
+	 * Returns the paths at which libraries with the given name would be found
+	 * inside an APK file, for all architectures supported by the device, in
+	 * order of preference.
+	 */
+	private List<String> getSupportedLibraryPaths(String libName) {
+		List<String> architectures = new ArrayList<>();
+		for (String abi : AndroidUtils.getSupportedArchitectures()) {
+			if (LIBRARY_ARCHITECTURES.contains(abi)) {
+				architectures.add("lib/" + abi + "/" + libName);
+			}
+		}
+		return architectures;
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/AndroidTorPluginFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/AndroidTorPluginFactory.java
@@ -0,0 +1,140 @@
+package org.briarproject.bramble.plugin.tor;
+
+import android.app.Application;
+
+import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.lifecycle.IoExecutor;
+import org.briarproject.bramble.api.network.NetworkManager;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.Backoff;
+import org.briarproject.bramble.api.plugin.BackoffFactory;
+import org.briarproject.bramble.api.plugin.PluginCallback;
+import org.briarproject.bramble.api.plugin.TorConstants;
+import org.briarproject.bramble.api.plugin.TorDirectory;
+import org.briarproject.bramble.api.plugin.TransportId;
+import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
+import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.bramble.api.system.LocationUtils;
+import org.briarproject.bramble.api.system.ResourceProvider;
+import org.briarproject.bramble.api.system.WakefulIoExecutor;
+import org.briarproject.bramble.util.AndroidUtils;
+
+import java.io.File;
+import java.util.concurrent.Executor;
+import java.util.logging.Logger;
+
+import javax.annotation.concurrent.Immutable;
+import javax.inject.Inject;
+import javax.net.SocketFactory;
+
+@Immutable
+@NotNullByDefault
+public class AndroidTorPluginFactory implements DuplexPluginFactory {
+
+	private static final Logger LOG =
+			Logger.getLogger(AndroidTorPluginFactory.class.getName());
+
+	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
+	private static final int MAX_IDLE_TIME = 30 * 1000; // 30 seconds
+	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
+	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
+	private static final double BACKOFF_BASE = 1.2;
+
+	private final Executor ioExecutor, wakefulIoExecutor;
+	private final Application app;
+	private final NetworkManager networkManager;
+	private final LocationUtils locationUtils;
+	private final EventBus eventBus;
+	private final SocketFactory torSocketFactory;
+	private final BackoffFactory backoffFactory;
+	private final ResourceProvider resourceProvider;
+	private final CircumventionProvider circumventionProvider;
+	private final BatteryManager batteryManager;
+	private final AndroidWakeLockManager wakeLockManager;
+	private final Clock clock;
+	private final File torDirectory;
+
+	@Inject
+	public AndroidTorPluginFactory(@IoExecutor Executor ioExecutor,
+			@WakefulIoExecutor Executor wakefulIoExecutor,
+			Application app,
+			NetworkManager networkManager,
+			LocationUtils locationUtils,
+			EventBus eventBus,
+			SocketFactory torSocketFactory,
+			BackoffFactory backoffFactory,
+			ResourceProvider resourceProvider,
+			CircumventionProvider circumventionProvider,
+			BatteryManager batteryManager,
+			AndroidWakeLockManager wakeLockManager,
+			Clock clock,
+			@TorDirectory File torDirectory) {
+		this.ioExecutor = ioExecutor;
+		this.wakefulIoExecutor = wakefulIoExecutor;
+		this.app = app;
+		this.networkManager = networkManager;
+		this.locationUtils = locationUtils;
+		this.eventBus = eventBus;
+		this.torSocketFactory = torSocketFactory;
+		this.backoffFactory = backoffFactory;
+		this.resourceProvider = resourceProvider;
+		this.circumventionProvider = circumventionProvider;
+		this.batteryManager = batteryManager;
+		this.wakeLockManager = wakeLockManager;
+		this.clock = clock;
+		this.torDirectory = torDirectory;
+	}
+
+	@Override
+	public TransportId getId() {
+		return TorConstants.ID;
+	}
+
+	@Override
+	public int getMaxLatency() {
+		return MAX_LATENCY;
+	}
+
+	@Override
+	public DuplexPlugin createPlugin(PluginCallback callback) {
+
+		// Check that we have a Tor binary for this architecture
+		String architecture = null;
+		for (String abi : AndroidUtils.getSupportedArchitectures()) {
+			if (abi.startsWith("x86_64")) {
+				architecture = "x86_64";
+				break;
+			} else if (abi.startsWith("x86")) {
+				architecture = "x86";
+				break;
+			} else if (abi.startsWith("arm64")) {
+				architecture = "arm64";
+				break;
+			} else if (abi.startsWith("armeabi")) {
+				architecture = "arm";
+				break;
+			}
+		}
+		if (architecture == null) {
+			LOG.info("Tor is not supported on this architecture");
+			return null;
+		}
+		// Use position-independent executable
+		architecture += "_pie";
+
+		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
+				MAX_POLLING_INTERVAL, BACKOFF_BASE);
+		TorRendezvousCrypto torRendezvousCrypto = new TorRendezvousCryptoImpl();
+		AndroidTorPlugin plugin = new AndroidTorPlugin(ioExecutor,
+				wakefulIoExecutor, app, networkManager, locationUtils,
+				torSocketFactory, clock, resourceProvider,
+				circumventionProvider, batteryManager, wakeLockManager,
+				backoff, torRendezvousCrypto, callback, architecture,
+				MAX_LATENCY, MAX_IDLE_TIME, torDirectory);
+		eventBus.addListener(plugin);
+		return plugin;
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorNetworkMetadata.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorNetworkMetadata.java
@@ -1,18 +0,0 @@
-package org.briarproject.bramble.plugin.tor;
-
-import java.util.Arrays;
-import java.util.HashSet;
-import java.util.Set;
-
-class TorNetworkMetadata {
-
-	// See https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2
-	// and https://trac.torproject.org/projects/tor/wiki/doc/OONI/censorshipwiki
-	// TODO: get a more complete list
-	private static final Set<String> BLOCKED_IN_COUNTRIES =
-			new HashSet<>(Arrays.asList("CN", "IR", "SY", "ZZ"));
-
-	static boolean isTorProbablyBlocked(String countryCode) {
-		return BLOCKED_IN_COUNTRIES.contains(countryCode);
-	}
-}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPlugin.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPlugin.java
@@ -1,779 +0,0 @@
-package org.briarproject.bramble.plugin.tor;
-
-import android.content.BroadcastReceiver;
-import android.content.Context;
-import android.content.Intent;
-import android.content.IntentFilter;
-import android.content.pm.PackageInfo;
-import android.content.pm.PackageManager;
-import android.content.pm.PackageManager.NameNotFoundException;
-import android.content.res.Resources;
-import android.net.ConnectivityManager;
-import android.net.NetworkInfo;
-import android.os.FileObserver;
-import android.os.PowerManager;
-
-import net.freehaven.tor.control.EventHandler;
-import net.freehaven.tor.control.TorControlConnection;
-
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.crypto.PseudoRandom;
-import org.briarproject.bramble.api.data.BdfList;
-import org.briarproject.bramble.api.event.Event;
-import org.briarproject.bramble.api.event.EventListener;
-import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
-import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
-import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
-import org.briarproject.bramble.api.plugin.Backoff;
-import org.briarproject.bramble.api.plugin.PluginException;
-import org.briarproject.bramble.api.plugin.TorConstants;
-import org.briarproject.bramble.api.plugin.TransportId;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
-import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
-import org.briarproject.bramble.api.properties.TransportProperties;
-import org.briarproject.bramble.api.reporting.DevReporter;
-import org.briarproject.bramble.api.settings.Settings;
-import org.briarproject.bramble.api.settings.event.SettingsUpdatedEvent;
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.util.AndroidUtils;
-import org.briarproject.bramble.util.IoUtils;
-import org.briarproject.bramble.util.StringUtils;
-
-import java.io.Closeable;
-import java.io.EOFException;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.net.InetSocketAddress;
-import java.net.ServerSocket;
-import java.net.Socket;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
-import java.util.Scanner;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.Executor;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.logging.Logger;
-import java.util.regex.Pattern;
-import java.util.zip.ZipInputStream;
-
-import javax.annotation.Nullable;
-import javax.net.SocketFactory;
-
-import static android.content.Context.CONNECTIVITY_SERVICE;
-import static android.content.Context.MODE_PRIVATE;
-import static android.content.Context.POWER_SERVICE;
-import static android.net.ConnectivityManager.CONNECTIVITY_ACTION;
-import static android.net.ConnectivityManager.TYPE_WIFI;
-import static android.os.PowerManager.PARTIAL_WAKE_LOCK;
-import static java.util.concurrent.TimeUnit.MILLISECONDS;
-import static java.util.logging.Level.INFO;
-import static java.util.logging.Level.WARNING;
-import static net.freehaven.tor.control.TorControlCommands.HS_ADDRESS;
-import static net.freehaven.tor.control.TorControlCommands.HS_PRIVKEY;
-import static org.briarproject.bramble.api.plugin.TorConstants.CONTROL_PORT;
-import static org.briarproject.bramble.api.plugin.TorConstants.ID;
-import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK;
-import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK_ALWAYS;
-import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK_NEVER;
-import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK_WIFI;
-import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_PORT;
-import static org.briarproject.bramble.util.PrivacyUtils.scrubOnion;
-
-@MethodsNotNullByDefault
-@ParametersNotNullByDefault
-class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
-
-	private static final String PROP_ONION = "onion";
-	private static final String[] EVENTS = {
-			"CIRC", "ORCONN", "HS_DESC", "NOTICE", "WARN", "ERR"
-	};
-	private static final String OWNER = "__OwningControllerProcess";
-	private static final int COOKIE_TIMEOUT = 3000; // Milliseconds
-	private static final Pattern ONION = Pattern.compile("[a-z2-7]{16}");
-	private static final Logger LOG =
-			Logger.getLogger(TorPlugin.class.getName());
-
-	private final Executor ioExecutor;
-	private final Context appContext;
-	private final LocationUtils locationUtils;
-	private final DevReporter reporter;
-	private final SocketFactory torSocketFactory;
-	private final Backoff backoff;
-	private final DuplexPluginCallback callback;
-	private final String architecture;
-	private final int maxLatency, maxIdleTime, socketTimeout;
-	private final ConnectionStatus connectionStatus;
-	private final File torDirectory, torFile, geoIpFile, configFile;
-	private final File doneFile, cookieFile;
-	private final PowerManager.WakeLock wakeLock;
-	private final AtomicBoolean used = new AtomicBoolean(false);
-
-	private volatile boolean running = false;
-	private volatile ServerSocket socket = null;
-	private volatile Socket controlSocket = null;
-	private volatile TorControlConnection controlConnection = null;
-	private volatile BroadcastReceiver networkStateReceiver = null;
-
-	TorPlugin(Executor ioExecutor, Context appContext,
-			LocationUtils locationUtils, DevReporter reporter,
-			SocketFactory torSocketFactory, Backoff backoff,
-			DuplexPluginCallback callback, String architecture, int maxLatency,
-			int maxIdleTime) {
-		this.ioExecutor = ioExecutor;
-		this.appContext = appContext;
-		this.locationUtils = locationUtils;
-		this.reporter = reporter;
-		this.torSocketFactory = torSocketFactory;
-		this.backoff = backoff;
-		this.callback = callback;
-		this.architecture = architecture;
-		this.maxLatency = maxLatency;
-		this.maxIdleTime = maxIdleTime;
-		if (maxIdleTime > Integer.MAX_VALUE / 2)
-			socketTimeout = Integer.MAX_VALUE;
-		else socketTimeout = maxIdleTime * 2;
-		connectionStatus = new ConnectionStatus();
-		torDirectory = appContext.getDir("tor", MODE_PRIVATE);
-		torFile = new File(torDirectory, "tor");
-		geoIpFile = new File(torDirectory, "geoip");
-		configFile = new File(torDirectory, "torrc");
-		doneFile = new File(torDirectory, "done");
-		cookieFile = new File(torDirectory, ".tor/control_auth_cookie");
-		Object o = appContext.getSystemService(POWER_SERVICE);
-		PowerManager pm = (PowerManager) o;
-		wakeLock = pm.newWakeLock(PARTIAL_WAKE_LOCK, "TorPlugin");
-		wakeLock.setReferenceCounted(false);
-	}
-
-	@Override
-	public TransportId getId() {
-		return TorConstants.ID;
-	}
-
-	@Override
-	public int getMaxLatency() {
-		return maxLatency;
-	}
-
-	@Override
-	public int getMaxIdleTime() {
-		return maxIdleTime;
-	}
-
-	@Override
-	public void start() throws PluginException {
-		if (used.getAndSet(true)) throw new IllegalStateException();
-		// Install or update the assets if necessary
-		if (!assetsAreUpToDate()) installAssets();
-		LOG.info("Starting Tor");
-		// Watch for the auth cookie file being updated
-		try {
-			cookieFile.getParentFile().mkdirs();
-			cookieFile.createNewFile();
-		} catch (IOException e) {
-			throw new PluginException(e);
-		}
-		CountDownLatch latch = new CountDownLatch(1);
-		FileObserver obs = new WriteObserver(cookieFile, latch);
-		obs.startWatching();
-		// Start a new Tor process
-		String torPath = torFile.getAbsolutePath();
-		String configPath = configFile.getAbsolutePath();
-		String pid = String.valueOf(android.os.Process.myPid());
-		Process torProcess;
-		ProcessBuilder pb =
-				new ProcessBuilder(torPath, "-f", configPath, OWNER, pid);
-		Map<String, String> env = pb.environment();
-		env.put("HOME", torDirectory.getAbsolutePath());
-		pb.directory(torDirectory);
-		try {
-			torProcess = pb.start();
-		} catch (SecurityException | IOException e) {
-			throw new PluginException(e);
-		}
-		// Log the process's standard output until it detaches
-		if (LOG.isLoggable(INFO)) {
-			Scanner stdout = new Scanner(torProcess.getInputStream());
-			Scanner stderr = new Scanner(torProcess.getErrorStream());
-			while (stdout.hasNextLine() || stderr.hasNextLine()){
-				if(stdout.hasNextLine()) {
-					LOG.info(stdout.nextLine());
-				}
-				if(stderr.hasNextLine()){
-					LOG.info(stderr.nextLine());
-				}
-			}
-			stdout.close();
-			stderr.close();
-		}
-		try {
-			// Wait for the process to detach or exit
-			int exit = torProcess.waitFor();
-			if (exit != 0) {
-				if (LOG.isLoggable(WARNING))
-					LOG.warning("Tor exited with value " + exit);
-				throw new PluginException();
-			}
-			// Wait for the auth cookie file to be created/updated
-			if (!latch.await(COOKIE_TIMEOUT, MILLISECONDS)) {
-				LOG.warning("Auth cookie not created");
-				if (LOG.isLoggable(INFO)) listFiles(torDirectory);
-				throw new PluginException();
-			}
-		} catch (InterruptedException e) {
-			LOG.warning("Interrupted while starting Tor");
-			Thread.currentThread().interrupt();
-			throw new PluginException();
-		}
-		try {
-			// Open a control connection and authenticate using the cookie file
-			controlSocket = new Socket("127.0.0.1", CONTROL_PORT);
-			controlConnection = new TorControlConnection(controlSocket);
-			controlConnection.authenticate(read(cookieFile));
-			// Tell Tor to exit when the control connection is closed
-			controlConnection.takeOwnership();
-			controlConnection.resetConf(Collections.singletonList(OWNER));
-			running = true;
-			// Register to receive events from the Tor process
-			controlConnection.setEventHandler(this);
-			controlConnection.setEvents(Arrays.asList(EVENTS));
-			// Check whether Tor has already bootstrapped
-			String phase = controlConnection.getInfo("status/bootstrap-phase");
-			if (phase != null && phase.contains("PROGRESS=100")) {
-				LOG.info("Tor has already bootstrapped");
-				connectionStatus.setBootstrapped();
-			}
-		} catch (IOException e) {
-			throw new PluginException(e);
-		}
-		// Register to receive network status events
-		networkStateReceiver = new NetworkStateReceiver();
-		IntentFilter filter = new IntentFilter(CONNECTIVITY_ACTION);
-		appContext.registerReceiver(networkStateReceiver, filter);
-		// Bind a server socket to receive incoming hidden service connections
-		bind();
-	}
-
-	private boolean assetsAreUpToDate() {
-		try {
-			PackageManager pm = appContext.getPackageManager();
-			PackageInfo pi = pm.getPackageInfo(appContext.getPackageName(), 0);
-			return doneFile.lastModified() > pi.lastUpdateTime;
-		} catch (NameNotFoundException e) {
-			throw new RuntimeException(e);
-		}
-	}
-
-	private void installAssets() throws PluginException {
-		InputStream in = null;
-		OutputStream out = null;
-		try {
-			doneFile.delete();
-			// Unzip the Tor binary to the filesystem
-			in = getTorInputStream();
-			out = new FileOutputStream(torFile);
-			IoUtils.copyAndClose(in, out);
-			// Make the Tor binary executable
-			if (!torFile.setExecutable(true, true)) throw new IOException();
-			// Unzip the GeoIP database to the filesystem
-			in = getGeoIpInputStream();
-			out = new FileOutputStream(geoIpFile);
-			IoUtils.copyAndClose(in, out);
-			// Copy the config file to the filesystem
-			in = getConfigInputStream();
-			out = new FileOutputStream(configFile);
-			IoUtils.copyAndClose(in, out);
-			doneFile.createNewFile();
-		} catch (IOException e) {
-			tryToClose(in);
-			tryToClose(out);
-			throw new PluginException(e);
-		}
-	}
-
-	private InputStream getTorInputStream() throws IOException {
-		if (LOG.isLoggable(INFO))
-			LOG.info("Installing Tor binary for " + architecture);
-		int resId = getResourceId("tor_" + architecture);
-		InputStream in = appContext.getResources().openRawResource(resId);
-		ZipInputStream zin = new ZipInputStream(in);
-		if (zin.getNextEntry() == null) throw new IOException();
-		return zin;
-	}
-
-	private InputStream getGeoIpInputStream() throws IOException {
-		int resId = getResourceId("geoip");
-		InputStream in = appContext.getResources().openRawResource(resId);
-		ZipInputStream zin = new ZipInputStream(in);
-		if (zin.getNextEntry() == null) throw new IOException();
-		return zin;
-	}
-
-	private InputStream getConfigInputStream() throws IOException {
-		int resId = getResourceId("torrc");
-		return appContext.getResources().openRawResource(resId);
-	}
-
-	private int getResourceId(String filename) {
-		Resources res = appContext.getResources();
-		return res.getIdentifier(filename, "raw", appContext.getPackageName());
-	}
-
-	private void tryToClose(@Nullable Closeable c) {
-		try {
-			if (c != null) c.close();
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-		}
-	}
-
-	private void tryToClose(@Nullable Socket s) {
-		try {
-			if (s != null) s.close();
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-		}
-	}
-
-	private void listFiles(File f) {
-		if (f.isDirectory()) {
-			File[] children = f.listFiles();
-			if (children != null) for (File child : children) listFiles(child);
-		} else {
-			LOG.info(f.getAbsolutePath());
-		}
-	}
-
-	private byte[] read(File f) throws IOException {
-		byte[] b = new byte[(int) f.length()];
-		FileInputStream in = new FileInputStream(f);
-		try {
-			int offset = 0;
-			while (offset < b.length) {
-				int read = in.read(b, offset, b.length - offset);
-				if (read == -1) throw new EOFException();
-				offset += read;
-			}
-			return b;
-		} finally {
-			tryToClose(in);
-		}
-	}
-
-	private void sendDevReports() {
-		ioExecutor.execute(new Runnable() {
-			@Override
-			public void run() {
-				// TODO: Trigger this with a TransportEnabledEvent
-				File reportDir = AndroidUtils.getReportDir(appContext);
-				reporter.sendReports(reportDir);
-			}
-		});
-	}
-
-	private void bind() {
-		ioExecutor.execute(new Runnable() {
-			@Override
-			public void run() {
-				// If there's already a port number stored in config, reuse it
-				String portString = callback.getSettings().get(PREF_TOR_PORT);
-				int port;
-				if (StringUtils.isNullOrEmpty(portString)) port = 0;
-				else port = Integer.parseInt(portString);
-				// Bind a server socket to receive connections from Tor
-				ServerSocket ss = null;
-				try {
-					ss = new ServerSocket();
-					ss.bind(new InetSocketAddress("127.0.0.1", port));
-				} catch (IOException e) {
-					if (LOG.isLoggable(WARNING))
-						LOG.log(WARNING, e.toString(), e);
-					tryToClose(ss);
-					return;
-				}
-				if (!running) {
-					tryToClose(ss);
-					return;
-				}
-				socket = ss;
-				// Store the port number
-				final String localPort = String.valueOf(ss.getLocalPort());
-				Settings s = new Settings();
-				s.put(PREF_TOR_PORT, localPort);
-				callback.mergeSettings(s);
-				// Create a hidden service if necessary
-				ioExecutor.execute(new Runnable() {
-					@Override
-					public void run() {
-						publishHiddenService(localPort);
-					}
-				});
-				backoff.reset();
-				// Accept incoming hidden service connections from Tor
-				acceptContactConnections(ss);
-			}
-		});
-	}
-
-	private void tryToClose(@Nullable ServerSocket ss) {
-		try {
-			if (ss != null) ss.close();
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-		} finally {
-			callback.transportDisabled();
-		}
-	}
-
-	private void publishHiddenService(String port) {
-		if (!running) return;
-		LOG.info("Creating hidden service");
-		String privKey = callback.getSettings().get(HS_PRIVKEY);
-		Map<Integer, String> portLines =
-				Collections.singletonMap(80, "127.0.0.1:" + port);
-		Map<String, String> response;
-		try {
-			// Use the control connection to set up the hidden service
-			if (privKey == null)
-				response = controlConnection.addOnion(portLines);
-			else response = controlConnection.addOnion(privKey, portLines);
-		} catch (IOException e) {
-			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			return;
-		}
-		if (!response.containsKey(HS_ADDRESS)) {
-			LOG.warning("Tor did not return a hidden service address");
-			return;
-		}
-		if (privKey == null && !response.containsKey(HS_PRIVKEY)) {
-			LOG.warning("Tor did not return a private key");
-			return;
-		}
-		// Publish the hidden service's onion hostname in transport properties
-		String hostname = response.get(HS_ADDRESS);
-		if (LOG.isLoggable(INFO))
-			LOG.info("Hidden service " + scrubOnion(hostname));
-		TransportProperties p = new TransportProperties();
-		p.put(PROP_ONION, hostname);
-		callback.mergeLocalProperties(p);
-		if (privKey == null) {
-			// Save the hidden service's private key for next time
-			Settings s = new Settings();
-			s.put(HS_PRIVKEY, response.get(HS_PRIVKEY));
-			callback.mergeSettings(s);
-		}
-	}
-
-	private void acceptContactConnections(ServerSocket ss) {
-		while (running) {
-			Socket s;
-			try {
-				s = ss.accept();
-				s.setSoTimeout(socketTimeout);
-			} catch (IOException e) {
-				// This is expected when the socket is closed
-				if (LOG.isLoggable(INFO)) LOG.info(e.toString());
-				return;
-			}
-			LOG.info("Connection received");
-			backoff.reset();
-			TorTransportConnection conn = new TorTransportConnection(this, s);
-			callback.incomingConnectionCreated(conn);
-		}
-	}
-
-	private void enableNetwork(boolean enable) throws IOException {
-		if (!running) return;
-		if (enable) wakeLock.acquire();
-		connectionStatus.enableNetwork(enable);
-		controlConnection.setConf("DisableNetwork", enable ? "0" : "1");
-		if (!enable) {
-			callback.transportDisabled();
-			wakeLock.release();
-		}
-	}
-
-	@Override
-	public void stop() throws PluginException {
-		running = false;
-		tryToClose(socket);
-		if (networkStateReceiver != null)
-			appContext.unregisterReceiver(networkStateReceiver);
-		if (controlSocket != null && controlConnection != null) {
-			try {
-				LOG.info("Stopping Tor");
-				controlConnection.setConf("DisableNetwork", "1");
-				controlConnection.shutdownTor("TERM");
-				controlSocket.close();
-			} catch (IOException e) {
-				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			}
-		}
-		wakeLock.release();
-	}
-
-	@Override
-	public boolean isRunning() {
-		return running && connectionStatus.isConnected();
-	}
-
-	@Override
-	public boolean shouldPoll() {
-		return true;
-	}
-
-	@Override
-	public int getPollingInterval() {
-		return backoff.getPollingInterval();
-	}
-
-	@Override
-	public void poll(Collection<ContactId> connected) {
-		if (!isRunning()) return;
-		backoff.increment();
-		// TODO: Pass properties to connectAndCallBack()
-		for (ContactId c : callback.getRemoteProperties().keySet())
-			if (!connected.contains(c)) connectAndCallBack(c);
-	}
-
-	private void connectAndCallBack(final ContactId c) {
-		ioExecutor.execute(new Runnable() {
-			@Override
-			public void run() {
-				DuplexTransportConnection d = createConnection(c);
-				if (d != null) {
-					backoff.reset();
-					callback.outgoingConnectionCreated(c, d);
-				}
-			}
-		});
-	}
-
-	@Override
-	public DuplexTransportConnection createConnection(ContactId c) {
-		if (!isRunning()) return null;
-		TransportProperties p = callback.getRemoteProperties().get(c);
-		if (p == null) return null;
-		String onion = p.get(PROP_ONION);
-		if (StringUtils.isNullOrEmpty(onion)) return null;
-		if (!ONION.matcher(onion).matches()) {
-			// not scrubbing this address, so we are able to find the problem
-			if (LOG.isLoggable(INFO)) LOG.info("Invalid hostname: " + onion);
-			return null;
-		}
-		Socket s = null;
-		try {
-			if (LOG.isLoggable(INFO))
-				LOG.info("Connecting to " + scrubOnion(onion));
-			controlConnection.forgetHiddenService(onion);
-			s = torSocketFactory.createSocket(onion + ".onion", 80);
-			s.setSoTimeout(socketTimeout);
-			if (LOG.isLoggable(INFO))
-				LOG.info("Connected to " + scrubOnion(onion));
-			return new TorTransportConnection(this, s);
-		} catch (IOException e) {
-			if (LOG.isLoggable(INFO)) {
-				LOG.info("Could not connect to " + scrubOnion(onion) + ": " +
-						e.toString());
-			}
-			tryToClose(s);
-			return null;
-		}
-	}
-
-	@Override
-	public boolean supportsInvitations() {
-		return false;
-	}
-
-	@Override
-	public DuplexTransportConnection createInvitationConnection(PseudoRandom r,
-			long timeout, boolean alice) {
-		throw new UnsupportedOperationException();
-	}
-
-	@Override
-	public boolean supportsKeyAgreement() {
-		return false;
-	}
-
-	@Override
-	public KeyAgreementListener createKeyAgreementListener(byte[] commitment) {
-		throw new UnsupportedOperationException();
-	}
-
-	@Override
-	public DuplexTransportConnection createKeyAgreementConnection(
-			byte[] commitment, BdfList descriptor, long timeout) {
-		throw new UnsupportedOperationException();
-	}
-
-	@Override
-	public void circuitStatus(String status, String id, String path) {
-		if (status.equals("BUILT") &&
-				connectionStatus.getAndSetCircuitBuilt()) {
-			LOG.info("First circuit built");
-			backoff.reset();
-			if (isRunning()) {
-				sendDevReports();
-				callback.transportEnabled();
-			}
-		}
-	}
-
-	@Override
-	public void streamStatus(String status, String id, String target) {
-	}
-
-	@Override
-	public void orConnStatus(String status, String orName) {
-		if (LOG.isLoggable(INFO)) LOG.info("OR connection " + status);
-	}
-
-	@Override
-	public void bandwidthUsed(long read, long written) {
-	}
-
-	@Override
-	public void newDescriptors(List<String> orList) {
-	}
-
-	@Override
-	public void message(String severity, String msg) {
-		if (LOG.isLoggable(INFO)) LOG.info(severity + " " + msg);
-		if (severity.equals("NOTICE") && msg.startsWith("Bootstrapped 100%")) {
-			connectionStatus.setBootstrapped();
-			backoff.reset();
-			if (isRunning()) {
-				sendDevReports();
-				callback.transportEnabled();
-			}
-		}
-	}
-
-	@Override
-	public void unrecognized(String type, String msg) {
-		if (type.equals("HS_DESC") && msg.startsWith("UPLOADED"))
-			LOG.info("Descriptor uploaded");
-	}
-
-	private static class WriteObserver extends FileObserver {
-
-		private final CountDownLatch latch;
-
-		private WriteObserver(File file, CountDownLatch latch) {
-			super(file.getAbsolutePath(), CLOSE_WRITE);
-			this.latch = latch;
-		}
-
-		@Override
-		public void onEvent(int event, String path) {
-			stopWatching();
-			latch.countDown();
-		}
-	}
-
-	@Override
-	public void eventOccurred(Event e) {
-		if (e instanceof SettingsUpdatedEvent) {
-			SettingsUpdatedEvent s = (SettingsUpdatedEvent) e;
-			if (s.getNamespace().equals(ID.getString())) {
-				LOG.info("Tor settings updated");
-				updateConnectionStatus();
-			}
-		}
-	}
-
-	private void updateConnectionStatus() {
-		ioExecutor.execute(new Runnable() {
-			@Override
-			public void run() {
-				if (!running) return;
-
-				Object o = appContext.getSystemService(CONNECTIVITY_SERVICE);
-				ConnectivityManager cm = (ConnectivityManager) o;
-				NetworkInfo net = cm.getActiveNetworkInfo();
-				boolean online = net != null && net.isConnected();
-				boolean wifi = online && net.getType() == TYPE_WIFI;
-				String country = locationUtils.getCurrentCountry();
-				boolean blocked = TorNetworkMetadata.isTorProbablyBlocked(
-						country);
-				Settings s = callback.getSettings();
-				int network = s.getInt(PREF_TOR_NETWORK,
-						PREF_TOR_NETWORK_ALWAYS);
-
-				if (LOG.isLoggable(INFO)) {
-					LOG.info("Online: " + online + ", wifi: " + wifi);
-					if ("".equals(country)) LOG.info("Country code unknown");
-					else LOG.info("Country code: " + country);
-				}
-
-				try {
-					if (!online) {
-						LOG.info("Disabling network, device is offline");
-						enableNetwork(false);
-					} else if (blocked) {
-						LOG.info("Disabling network, country is blocked");
-						enableNetwork(false);
-					} else if (network == PREF_TOR_NETWORK_NEVER
-							|| (network == PREF_TOR_NETWORK_WIFI && !wifi)) {
-						LOG.info("Disabling network due to data setting");
-						enableNetwork(false);
-					} else {
-						LOG.info("Enabling network");
-						enableNetwork(true);
-					}
-				} catch (IOException e) {
-					if (LOG.isLoggable(WARNING))
-						LOG.log(WARNING, e.toString(), e);
-				}
-			}
-		});
-	}
-
-	private class NetworkStateReceiver extends BroadcastReceiver {
-
-		@Override
-		public void onReceive(Context ctx, Intent i) {
-			if (!running) return;
-			if (CONNECTIVITY_ACTION.equals(i.getAction())) {
-				LOG.info("Detected connectivity change");
-				updateConnectionStatus();
-			}
-		}
-	}
-
-	private static class ConnectionStatus {
-
-		// All of the following are locking: this
-		private boolean networkEnabled = false;
-		private boolean bootstrapped = false, circuitBuilt = false;
-
-		private synchronized void setBootstrapped() {
-			bootstrapped = true;
-		}
-
-		private synchronized boolean getAndSetCircuitBuilt() {
-			boolean firstCircuit = !circuitBuilt;
-			circuitBuilt = true;
-			return firstCircuit;
-		}
-
-		private synchronized void enableNetwork(boolean enable) {
-			networkEnabled = enable;
-			circuitBuilt = false;
-		}
-
-		private synchronized boolean isConnected() {
-			return networkEnabled && bootstrapped && circuitBuilt;
-		}
-	}
-}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPluginFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPluginFactory.java
@@ -1,98 +0,0 @@
-package org.briarproject.bramble.plugin.tor;
-
-import android.content.Context;
-import android.os.Build;
-
-import org.briarproject.bramble.api.event.EventBus;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.plugin.Backoff;
-import org.briarproject.bramble.api.plugin.BackoffFactory;
-import org.briarproject.bramble.api.plugin.TorConstants;
-import org.briarproject.bramble.api.plugin.TransportId;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
-import org.briarproject.bramble.api.reporting.DevReporter;
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.util.AndroidUtils;
-
-import java.util.concurrent.Executor;
-import java.util.logging.Logger;
-
-import javax.annotation.concurrent.Immutable;
-import javax.net.SocketFactory;
-
-@Immutable
-@NotNullByDefault
-public class TorPluginFactory implements DuplexPluginFactory {
-
-	private static final Logger LOG =
-			Logger.getLogger(TorPluginFactory.class.getName());
-
-	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
-	private static final int MAX_IDLE_TIME = 30 * 1000; // 30 seconds
-	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
-	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
-	private static final double BACKOFF_BASE = 1.2;
-
-	private final Executor ioExecutor;
-	private final Context appContext;
-	private final LocationUtils locationUtils;
-	private final DevReporter reporter;
-	private final EventBus eventBus;
-	private final SocketFactory torSocketFactory;
-	private final BackoffFactory backoffFactory;
-
-	public TorPluginFactory(Executor ioExecutor, Context appContext,
-			LocationUtils locationUtils, DevReporter reporter,
-			EventBus eventBus, SocketFactory torSocketFactory,
-			BackoffFactory backoffFactory) {
-		this.ioExecutor = ioExecutor;
-		this.appContext = appContext;
-		this.locationUtils = locationUtils;
-		this.reporter = reporter;
-		this.eventBus = eventBus;
-		this.torSocketFactory = torSocketFactory;
-		this.backoffFactory = backoffFactory;
-	}
-
-	@Override
-	public TransportId getId() {
-		return TorConstants.ID;
-	}
-
-	@Override
-	public int getMaxLatency() {
-		return MAX_LATENCY;
-	}
-
-	@Override
-	public DuplexPlugin createPlugin(DuplexPluginCallback callback) {
-
-		// Check that we have a Tor binary for this architecture
-		String architecture = null;
-		for (String abi : AndroidUtils.getSupportedArchitectures()) {
-			if (abi.startsWith("x86")) {
-				architecture = "x86";
-				break;
-			} else if (abi.startsWith("armeabi")) {
-				architecture = "arm";
-				break;
-			}
-		}
-		if (architecture == null) {
-			LOG.info("Tor is not supported on this architecture");
-			return null;
-		}
-		// Use position-independent executable for SDK >= 16
-		if (Build.VERSION.SDK_INT >= 16) architecture += "_pie";
-
-		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
-				MAX_POLLING_INTERVAL, BACKOFF_BASE);
-		TorPlugin plugin = new TorPlugin(ioExecutor, appContext, locationUtils,
-				reporter, torSocketFactory, backoff, callback, architecture,
-				MAX_LATENCY, MAX_IDLE_TIME);
-		eventBus.addListener(plugin);
-		return plugin;
-	}
-}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AlarmConstants.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AlarmConstants.java
@@ -0,0 +1,18 @@
+package org.briarproject.bramble.system;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+interface AlarmConstants {
+
+	/**
+	 * Request code for the broadcast intent attached to the periodic alarm.
+	 */
+	int REQUEST_ALARM = 1;
+
+	/**
+	 * Key for storing the process ID in the extras of the periodic alarm's
+	 * intent. This allows us to ignore alarms scheduled by dead processes.
+	 */
+	String EXTRA_PID = "org.briarproject.bramble.EXTRA_PID";
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AlarmReceiver.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AlarmReceiver.java
@@ -0,0 +1,17 @@
+package org.briarproject.bramble.system;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+
+import org.briarproject.bramble.BrambleApplication;
+
+public class AlarmReceiver extends BroadcastReceiver {
+
+	@Override
+	public void onReceive(Context ctx, Intent intent) {
+		BrambleApplication app =
+				(BrambleApplication) ctx.getApplicationContext();
+		app.getBrambleAppComponent().alarmListener().onAlarm(intent);
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidExecutorImpl.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidExecutorImpl.java
@@ -27,14 +27,11 @@ class AndroidExecutorImpl implements AndroidExecutor {
 	@Inject
 	AndroidExecutorImpl(Application app) {
 		uiHandler = new Handler(app.getApplicationContext().getMainLooper());
-		loop = new Runnable() {
-			@Override
-			public void run() {
-				Looper.prepare();
-				backgroundHandler = new Handler();
-				startLatch.countDown();
-				Looper.loop();
-			}
+		loop = () -> {
+			Looper.prepare();
+			backgroundHandler = new Handler();
+			startLatch.countDown();
+			Looper.loop();
 		};
 	}

--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidLocationUtils.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidLocationUtils.java
@@ -61,12 +61,12 @@ class AndroidLocationUtils implements LocationUtils {
 	private String getCountryFromPhoneNetwork() {
 		Object o = appContext.getSystemService(TELEPHONY_SERVICE);
 		TelephonyManager tm = (TelephonyManager) o;
-		return tm.getNetworkCountryIso();
+		return tm == null ? "" : tm.getNetworkCountryIso();
 	}

 	private String getCountryFromSimCard() {
 		Object o = appContext.getSystemService(TELEPHONY_SERVICE);
 		TelephonyManager tm = (TelephonyManager) o;
-		return tm.getSimCountryIso();
+		return tm == null ? "" : tm.getSimCountryIso();
 	}
 }
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidResourceProvider.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidResourceProvider.java
@@ -0,0 +1,32 @@
+package org.briarproject.bramble.system;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.res.Resources;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.system.ResourceProvider;
+
+import java.io.InputStream;
+
+import javax.inject.Inject;
+
+@NotNullByDefault
+class AndroidResourceProvider implements ResourceProvider {
+
+	private final Context appContext;
+
+	@Inject
+	AndroidResourceProvider(Application app) {
+		this.appContext = app.getApplicationContext();
+	}
+
+	@Override
+	public InputStream getResourceInputStream(String name, String extension) {
+		Resources res = appContext.getResources();
+		// extension is ignored on Android, resources are retrieved without it
+		int resId =
+				res.getIdentifier(name, "raw", appContext.getPackageName());
+		return res.openRawResource(resId);
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSecureRandomProvider.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSecureRandomProvider.java
@@ -1,31 +1,30 @@
 package org.briarproject.bramble.system;

+import android.annotation.SuppressLint;
 import android.app.Application;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothDevice;
 import android.content.ContentResolver;
 import android.content.Context;
-import android.net.wifi.WifiConfiguration;
-import android.net.wifi.WifiManager;
 import android.os.Build;
 import android.os.Parcel;
+import android.os.StrictMode;
 import android.provider.Settings;

 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;

 import java.io.DataOutputStream;
 import java.io.IOException;
-import java.util.List;

 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;

-import static android.content.Context.WIFI_SERVICE;
+import static android.os.Build.VERSION.SDK_INT;
 import static android.provider.Settings.Secure.ANDROID_ID;

@Immutable
@NotNullByDefault
-class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
+class AndroidSecureRandomProvider extends UnixSecureRandomProvider {

 	private static final int SEED_LENGTH = 32;

@@ -36,6 +35,7 @@ class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
 		appContext = app.getApplicationContext();
 	}

+	@SuppressLint("HardwareIds")
 	@Override
 	protected void writeToEntropyPool(DataOutputStream out) throws IOException {
 		super.writeToEntropyPool(out);
@@ -48,13 +48,6 @@ class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
 		String id = Settings.Secure.getString(contentResolver, ANDROID_ID);
 		if (id != null) out.writeUTF(id);
 		Parcel parcel = Parcel.obtain();
-		WifiManager wm =
-				(WifiManager) appContext.getSystemService(WIFI_SERVICE);
-		List<WifiConfiguration> configs = wm.getConfiguredNetworks();
-		if (configs != null) {
-			for (WifiConfiguration config : configs)
-				parcel.writeParcelable(config, 0);
-		}
 		BluetoothAdapter bt = BluetoothAdapter.getDefaultAdapter();
 		if (bt != null) {
 			for (BluetoothDevice device : bt.getBondedDevices())
@@ -66,20 +59,22 @@ class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {

 	@Override
 	protected void writeSeed() {
+		// Silence strict mode
+		StrictMode.ThreadPolicy tp = StrictMode.allowThreadDiskWrites();
 		super.writeSeed();
-		if (Build.VERSION.SDK_INT >= 16 && Build.VERSION.SDK_INT <= 18)
-			applyOpenSslFix();
+		if (SDK_INT <= 18) applyOpenSslFix();
+		StrictMode.setThreadPolicy(tp);
 	}

 	// Based on https://android-developers.googleblog.com/2013/08/some-securerandom-thoughts.html
 	private void applyOpenSslFix() {
-		byte[] seed = new LinuxSecureRandomSpi().engineGenerateSeed(
+		byte[] seed = new UnixSecureRandomSpi().engineGenerateSeed(
 				SEED_LENGTH);
 		try {
 			// Seed the OpenSSL PRNG
 			Class.forName("org.apache.harmony.xnet.provider.jsse.NativeCrypto")
 					.getMethod("RAND_seed", byte[].class)
-					.invoke(null, seed);
+					.invoke(null, (Object) seed);
 			// Mix the output of the Linux PRNG into the OpenSSL PRNG
 			int bytesRead = (Integer) Class.forName(
 					"org.apache.harmony.xnet.provider.jsse.NativeCrypto")
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSystemModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSystemModule.java
@@ -1,11 +1,18 @@
 package org.briarproject.bramble.system;

-import android.app.Application;
-
+import org.briarproject.bramble.api.event.EventExecutor;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.bramble.api.system.LocationUtils;
+import org.briarproject.bramble.api.system.ResourceProvider;
 import org.briarproject.bramble.api.system.SecureRandomProvider;

+import java.util.concurrent.Executor;
+import java.util.concurrent.RejectedExecutionHandler;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+
 import javax.inject.Singleton;

 import dagger.Module;
@@ -14,20 +21,59 @@ import dagger.Provides;
@Module
 public class AndroidSystemModule {

-	@Provides
-	@Singleton
-	SecureRandomProvider provideSecureRandomProvider(Application app) {
-		return new AndroidSecureRandomProvider(app);
-	}
+	private final ScheduledExecutorService scheduledExecutorService;

-	@Provides
-	LocationUtils provideLocationUtils(Application app) {
-		return new AndroidLocationUtils(app);
+	public AndroidSystemModule() {
+		// Discard tasks that are submitted during shutdown
+		RejectedExecutionHandler policy =
+				new ScheduledThreadPoolExecutor.DiscardPolicy();
+		scheduledExecutorService = new ScheduledThreadPoolExecutor(1, policy);
 	}

 	@Provides
 	@Singleton
-	AndroidExecutor provideAndroidExecutor(Application app) {
-		return new AndroidExecutorImpl(app);
+	ScheduledExecutorService provideScheduledExecutorService(
+			LifecycleManager lifecycleManager) {
+		lifecycleManager.registerForShutdown(scheduledExecutorService);
+		return scheduledExecutorService;
+	}
+
+	@Provides
+	@Singleton
+	SecureRandomProvider provideSecureRandomProvider(
+			AndroidSecureRandomProvider provider) {
+		return provider;
+	}
+
+	@Provides
+	LocationUtils provideLocationUtils(AndroidLocationUtils locationUtils) {
+		return locationUtils;
+	}
+
+	@Provides
+	@Singleton
+	AndroidExecutor provideAndroidExecutor(
+			AndroidExecutorImpl androidExecutor) {
+		return androidExecutor;
+	}
+
+	@Provides
+	@Singleton
+	@EventExecutor
+	Executor provideEventExecutor(AndroidExecutor androidExecutor) {
+		return androidExecutor::runOnUiThread;
+	}
+
+	@Provides
+	@Singleton
+	ResourceProvider provideResourceProvider(AndroidResourceProvider provider) {
+		return provider;
+	}
+
+	@Provides
+	@Singleton
+	AndroidWakeLockManager provideWakeLockManager(
+			AndroidWakeLockManagerImpl wakeLockManager) {
+		return wakeLockManager;
 	}
 }
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidTaskScheduler.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidTaskScheduler.java
@@ -0,0 +1,242 @@
+package org.briarproject.bramble.system;
+
+import android.annotation.TargetApi;
+import android.app.AlarmManager;
+import android.app.Application;
+import android.app.PendingIntent;
+import android.content.Intent;
+import android.os.Process;
+import android.os.SystemClock;
+
+import org.briarproject.bramble.api.lifecycle.Service;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.system.AlarmListener;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+import org.briarproject.bramble.api.system.TaskScheduler;
+import org.briarproject.bramble.api.system.Wakeful;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.PriorityQueue;
+import java.util.Queue;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.logging.Logger;
+
+import javax.annotation.concurrent.GuardedBy;
+import javax.annotation.concurrent.ThreadSafe;
+
+import static android.app.AlarmManager.ELAPSED_REALTIME_WAKEUP;
+import static android.app.AlarmManager.INTERVAL_FIFTEEN_MINUTES;
+import static android.app.PendingIntent.FLAG_CANCEL_CURRENT;
+import static android.content.Context.ALARM_SERVICE;
+import static android.os.Build.VERSION.SDK_INT;
+import static java.util.Objects.requireNonNull;
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.system.AlarmConstants.EXTRA_PID;
+import static org.briarproject.bramble.system.AlarmConstants.REQUEST_ALARM;
+
+@ThreadSafe
+@NotNullByDefault
+class AndroidTaskScheduler implements TaskScheduler, Service, AlarmListener {
+
+	private static final Logger LOG =
+			getLogger(AndroidTaskScheduler.class.getName());
+
+	private static final long ALARM_MS = INTERVAL_FIFTEEN_MINUTES;
+
+	private final Application app;
+	private final AndroidWakeLockManager wakeLockManager;
+	private final ScheduledExecutorService scheduledExecutorService;
+	private final AlarmManager alarmManager;
+
+	private final Object lock = new Object();
+	@GuardedBy("lock")
+	private final Queue<ScheduledTask> tasks = new PriorityQueue<>();
+
+	AndroidTaskScheduler(Application app,
+			AndroidWakeLockManager wakeLockManager,
+			ScheduledExecutorService scheduledExecutorService) {
+		this.app = app;
+		this.wakeLockManager = wakeLockManager;
+		this.scheduledExecutorService = scheduledExecutorService;
+		alarmManager = (AlarmManager)
+				requireNonNull(app.getSystemService(ALARM_SERVICE));
+	}
+
+	@Override
+	public void startService() {
+		scheduleAlarm();
+	}
+
+	@Override
+	public void stopService() {
+		cancelAlarm();
+	}
+
+	@Override
+	public Cancellable schedule(Runnable task, Executor executor, long delay,
+			TimeUnit unit) {
+		AtomicBoolean cancelled = new AtomicBoolean(false);
+		return schedule(task, executor, delay, unit, cancelled);
+	}
+
+	@Override
+	public Cancellable scheduleWithFixedDelay(Runnable task, Executor executor,
+			long delay, long interval, TimeUnit unit) {
+		AtomicBoolean cancelled = new AtomicBoolean(false);
+		return scheduleWithFixedDelay(task, executor, delay, interval, unit,
+				cancelled);
+	}
+
+	@Override
+	public void onAlarm(Intent intent) {
+		wakeLockManager.runWakefully(() -> {
+			int extraPid = intent.getIntExtra(EXTRA_PID, -1);
+			int currentPid = Process.myPid();
+			if (extraPid == currentPid) {
+				LOG.info("Alarm");
+				rescheduleAlarm();
+				runDueTasks();
+			} else if (LOG.isLoggable(INFO)) {
+				LOG.info("Ignoring alarm with PID " + extraPid
+						+ ", current PID is " + currentPid);
+			}
+		}, "TaskAlarm");
+	}
+
+	private Cancellable schedule(Runnable task, Executor executor, long delay,
+			TimeUnit unit, AtomicBoolean cancelled) {
+		long now = SystemClock.elapsedRealtime();
+		long dueMillis = now + MILLISECONDS.convert(delay, unit);
+		Runnable wakeful = () ->
+				wakeLockManager.executeWakefully(task, executor, "TaskHandoff");
+		Future<?> check = scheduleCheckForDueTasks(delay, unit);
+		ScheduledTask s = new ScheduledTask(wakeful, dueMillis, check,
+				cancelled);
+		synchronized (lock) {
+			tasks.add(s);
+		}
+		return s;
+	}
+
+	private Cancellable scheduleWithFixedDelay(Runnable task, Executor executor,
+			long delay, long interval, TimeUnit unit, AtomicBoolean cancelled) {
+		// All executions of this periodic task share a cancelled flag
+		Runnable wrapped = () -> {
+			task.run();
+			scheduleWithFixedDelay(task, executor, interval, interval, unit,
+					cancelled);
+		};
+		return schedule(wrapped, executor, delay, unit, cancelled);
+	}
+
+	private Future<?> scheduleCheckForDueTasks(long delay, TimeUnit unit) {
+		Runnable wakeful = () -> wakeLockManager.runWakefully(
+				this::runDueTasks, "TaskScheduler");
+		return scheduledExecutorService.schedule(wakeful, delay, unit);
+	}
+
+	@Wakeful
+	private void runDueTasks() {
+		long now = SystemClock.elapsedRealtime();
+		List<ScheduledTask> due = new ArrayList<>();
+		synchronized (lock) {
+			while (true) {
+				ScheduledTask s = tasks.peek();
+				if (s == null || s.dueMillis > now) break;
+				due.add(tasks.remove());
+			}
+		}
+		if (LOG.isLoggable(INFO)) {
+			LOG.info("Running " + due.size() + " due tasks");
+		}
+		for (ScheduledTask s : due) {
+			if (LOG.isLoggable(INFO)) {
+				LOG.info("Task is " + (now - s.dueMillis) + " ms overdue");
+			}
+			s.run();
+		}
+	}
+
+	private void scheduleAlarm() {
+		if (SDK_INT >= 23) scheduleIdleAlarm();
+		else scheduleInexactRepeatingAlarm();
+	}
+
+	private void rescheduleAlarm() {
+		// If SDK_INT < 23 the alarm repeats automatically
+		if (SDK_INT >= 23) scheduleIdleAlarm();
+	}
+
+	private void cancelAlarm() {
+		alarmManager.cancel(getAlarmPendingIntent());
+	}
+
+	private void scheduleInexactRepeatingAlarm() {
+		alarmManager.setInexactRepeating(ELAPSED_REALTIME_WAKEUP,
+				SystemClock.elapsedRealtime() + ALARM_MS, ALARM_MS,
+				getAlarmPendingIntent());
+	}
+
+	@TargetApi(23)
+	private void scheduleIdleAlarm() {
+		alarmManager.setAndAllowWhileIdle(ELAPSED_REALTIME_WAKEUP,
+				SystemClock.elapsedRealtime() + ALARM_MS,
+				getAlarmPendingIntent());
+	}
+
+	private PendingIntent getAlarmPendingIntent() {
+		Intent i = new Intent(app, AlarmReceiver.class);
+		i.putExtra(EXTRA_PID, android.os.Process.myPid());
+		return PendingIntent.getBroadcast(app, REQUEST_ALARM, i,
+				FLAG_CANCEL_CURRENT);
+	}
+
+	private class ScheduledTask
+			implements Runnable, Cancellable, Comparable<ScheduledTask> {
+
+		private final Runnable task;
+		private final long dueMillis;
+		private final Future<?> check;
+		private final AtomicBoolean cancelled;
+
+		public ScheduledTask(Runnable task, long dueMillis,
+				Future<?> check, AtomicBoolean cancelled) {
+			this.task = task;
+			this.dueMillis = dueMillis;
+			this.check = check;
+			this.cancelled = cancelled;
+		}
+
+		@Override
+		public void run() {
+			if (!cancelled.get()) task.run();
+		}
+
+		@Override
+		public void cancel() {
+			// Cancel any future executions of this task
+			cancelled.set(true);
+			// Cancel the scheduled check for due tasks
+			check.cancel(false);
+			// Remove the task from the queue
+			synchronized (lock) {
+				tasks.remove(this);
+			}
+		}
+
+		@Override
+		public int compareTo(ScheduledTask s) {
+			//noinspection UseCompareMethod
+			if (dueMillis < s.dueMillis) return -1;
+			if (dueMillis > s.dueMillis) return 1;
+			return 0;
+		}
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidTaskSchedulerModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidTaskSchedulerModule.java
@@ -0,0 +1,49 @@
+package org.briarproject.bramble.system;
+
+import android.app.Application;
+
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+import org.briarproject.bramble.api.system.AlarmListener;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+import org.briarproject.bramble.api.system.TaskScheduler;
+
+import java.util.concurrent.ScheduledExecutorService;
+
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class AndroidTaskSchedulerModule {
+
+	public static class EagerSingletons {
+		@Inject
+		AndroidTaskScheduler scheduler;
+	}
+
+	@Provides
+	@Singleton
+	AndroidTaskScheduler provideAndroidTaskScheduler(
+			LifecycleManager lifecycleManager, Application app,
+			AndroidWakeLockManager wakeLockManager,
+			ScheduledExecutorService scheduledExecutorService) {
+		AndroidTaskScheduler scheduler = new AndroidTaskScheduler(app,
+				wakeLockManager, scheduledExecutorService);
+		lifecycleManager.registerService(scheduler);
+		return scheduler;
+	}
+
+	@Provides
+	@Singleton
+	AlarmListener provideAlarmListener(AndroidTaskScheduler scheduler) {
+		return scheduler;
+	}
+
+	@Provides
+	@Singleton
+	TaskScheduler provideTaskScheduler(AndroidTaskScheduler scheduler) {
+		return scheduler;
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakeLockImpl.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakeLockImpl.java
@@ -0,0 +1,74 @@
+package org.briarproject.bramble.system;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.system.AndroidWakeLock;
+
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.logging.Logger;
+
+import javax.annotation.concurrent.GuardedBy;
+import javax.annotation.concurrent.ThreadSafe;
+
+import static java.util.logging.Level.FINE;
+import static java.util.logging.Logger.getLogger;
+
+/**
+ * A wrapper around a {@link SharedWakeLock} that provides the more convenient
+ * semantics of {@link AndroidWakeLock} (i.e. calls to acquire() and release()
+ * don't need to be balanced).
+ */
+@ThreadSafe
+@NotNullByDefault
+class AndroidWakeLockImpl implements AndroidWakeLock {
+
+	private static final Logger LOG =
+			getLogger(AndroidWakeLockImpl.class.getName());
+
+	private static final AtomicInteger INSTANCE_ID = new AtomicInteger(0);
+
+	private final SharedWakeLock sharedWakeLock;
+	private final String tag;
+
+	private final Object lock = new Object();
+	@GuardedBy("lock")
+	private boolean held = false;
+
+	AndroidWakeLockImpl(SharedWakeLock sharedWakeLock, String tag) {
+		this.sharedWakeLock = sharedWakeLock;
+		this.tag = tag + "_" + INSTANCE_ID.getAndIncrement();
+	}
+
+	@Override
+	public void acquire() {
+		synchronized (lock) {
+			if (held) {
+				if (LOG.isLoggable(FINE)) {
+					LOG.fine(tag + " already acquired");
+				}
+			} else {
+				if (LOG.isLoggable(FINE)) {
+					LOG.fine(tag + " acquiring shared wake lock");
+				}
+				held = true;
+				sharedWakeLock.acquire();
+			}
+		}
+	}
+
+	@Override
+	public void release() {
+		synchronized (lock) {
+			if (held) {
+				if (LOG.isLoggable(FINE)) {
+					LOG.fine(tag + " releasing shared wake lock");
+				}
+				held = false;
+				sharedWakeLock.release();
+			} else {
+				if (LOG.isLoggable(FINE)) {
+					LOG.fine(tag + " already released");
+				}
+			}
+		}
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakeLockManagerImpl.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakeLockManagerImpl.java
@@ -0,0 +1,125 @@
+package org.briarproject.bramble.system;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.PowerManager;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.system.AndroidWakeLock;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.ScheduledExecutorService;
+
+import javax.inject.Inject;
+
+import static android.content.Context.POWER_SERVICE;
+import static android.os.PowerManager.PARTIAL_WAKE_LOCK;
+import static java.util.concurrent.TimeUnit.MINUTES;
+import static java.util.concurrent.TimeUnit.SECONDS;
+import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+
+@NotNullByDefault
+class AndroidWakeLockManagerImpl implements AndroidWakeLockManager {
+
+	/**
+	 * How often to replace the wake lock.
+	 */
+	private static final long LOCK_DURATION_MS = MINUTES.toMillis(1);
+
+	/**
+	 * Automatically release the lock this many milliseconds after it's due
+	 * to have been replaced and released.
+	 */
+	private static final long SAFETY_MARGIN_MS = SECONDS.toMillis(30);
+
+	private final SharedWakeLock sharedWakeLock;
+
+	@Inject
+	AndroidWakeLockManagerImpl(Application app,
+			ScheduledExecutorService scheduledExecutorService) {
+		PowerManager powerManager = (PowerManager)
+				requireNonNull(app.getSystemService(POWER_SERVICE));
+		String tag = getWakeLockTag(app);
+		sharedWakeLock = new RenewableWakeLock(powerManager,
+				scheduledExecutorService, PARTIAL_WAKE_LOCK, tag,
+				LOCK_DURATION_MS, SAFETY_MARGIN_MS);
+	}
+
+	@Override
+	public AndroidWakeLock createWakeLock(String tag) {
+		return new AndroidWakeLockImpl(sharedWakeLock, tag);
+	}
+
+	@Override
+	public void runWakefully(Runnable r, String tag) {
+		AndroidWakeLock wakeLock = createWakeLock(tag);
+		wakeLock.acquire();
+		try {
+			r.run();
+		} finally {
+			wakeLock.release();
+		}
+	}
+
+	@Override
+	public void executeWakefully(Runnable r, Executor executor, String tag) {
+		AndroidWakeLock wakeLock = createWakeLock(tag);
+		wakeLock.acquire();
+		try {
+			executor.execute(() -> {
+				try {
+					r.run();
+				} finally {
+					// Release the wake lock if the task throws an exception
+					wakeLock.release();
+				}
+			});
+		} catch (Exception e) {
+			// Release the wake lock if the executor throws an exception when
+			// we submit the task (in which case the release() call above won't
+			// happen)
+			wakeLock.release();
+			throw e;
+		}
+	}
+
+	@Override
+	public void executeWakefully(Runnable r, String tag) {
+		AndroidWakeLock wakeLock = createWakeLock(tag);
+		wakeLock.acquire();
+		try {
+			new Thread(() -> {
+				try {
+					r.run();
+				} finally {
+					wakeLock.release();
+				}
+			}).start();
+		} catch (Exception e) {
+			wakeLock.release();
+			throw e;
+		}
+	}
+
+	private String getWakeLockTag(Context ctx) {
+		PackageManager pm = ctx.getPackageManager();
+		if (isInstalled(pm, "com.huawei.powergenie")) {
+			return "LocationManagerService";
+		} else if (isInstalled(pm, "com.evenwell.PowerMonitor")) {
+			return "AudioIn";
+		}
+		return ctx.getPackageName();
+	}
+
+	private boolean isInstalled(PackageManager pm, String packageName) {
+		try {
+			pm.getPackageInfo(packageName, 0);
+			return true;
+		} catch (PackageManager.NameNotFoundException e) {
+			return false;
+		}
+	}
+
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakefulIoExecutorModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakefulIoExecutorModule.java
@@ -0,0 +1,23 @@
+package org.briarproject.bramble.system;
+
+import org.briarproject.bramble.api.lifecycle.IoExecutor;
+import org.briarproject.bramble.api.system.AndroidWakeLockManager;
+import org.briarproject.bramble.api.system.WakefulIoExecutor;
+
+import java.util.concurrent.Executor;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public
+class AndroidWakefulIoExecutorModule {
+
+	@Provides
+	@WakefulIoExecutor
+	Executor provideWakefulIoExecutor(@IoExecutor Executor ioExecutor,
+			AndroidWakeLockManager wakeLockManager) {
+		return r -> wakeLockManager.executeWakefully(r, ioExecutor,
+				"WakefulIoExecutor");
+	}
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/RenewableWakeLock.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/RenewableWakeLock.java
@@ -0,0 +1,130 @@
+package org.briarproject.bramble.system;
+
+import android.os.PowerManager;
+import android.os.PowerManager.WakeLock;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.GuardedBy;
+import javax.annotation.concurrent.ThreadSafe;
+
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+import static java.util.logging.Level.FINE;
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+
+@ThreadSafe
+@NotNullByDefault
+class RenewableWakeLock implements SharedWakeLock {
+
+	private static final Logger LOG =
+			getLogger(RenewableWakeLock.class.getName());
+
+	private final PowerManager powerManager;
+	private final ScheduledExecutorService scheduledExecutorService;
+	private final int levelAndFlags;
+	private final String tag;
+	private final long durationMs, safetyMarginMs;
+
+	private final Object lock = new Object();
+	@GuardedBy("lock")
+	@Nullable
+	private WakeLock wakeLock;
+	@GuardedBy("lock")
+	@Nullable
+	private Future<?> future;
+	@GuardedBy("lock")
+	private int refCount = 0;
+	@GuardedBy("lock")
+	private long acquired = 0;
+
+	RenewableWakeLock(PowerManager powerManager,
+			ScheduledExecutorService scheduledExecutorService,
+			int levelAndFlags,
+			String tag,
+			long durationMs,
+			long safetyMarginMs) {
+		this.powerManager = powerManager;
+		this.scheduledExecutorService = scheduledExecutorService;
+		this.levelAndFlags = levelAndFlags;
+		this.tag = tag;
+		this.durationMs = durationMs;
+		this.safetyMarginMs = safetyMarginMs;
+	}
+
+	@Override
+	public void acquire() {
+		synchronized (lock) {
+			refCount++;
+			if (refCount == 1) {
+				if (LOG.isLoggable(INFO)) {
+					LOG.info("Acquiring wake lock " + tag);
+				}
+				wakeLock = powerManager.newWakeLock(levelAndFlags, tag);
+				// We do our own reference counting so we can replace the lock
+				// TODO: Check whether using a ref-counted wake lock affects
+				//  power management apps
+				wakeLock.setReferenceCounted(false);
+				wakeLock.acquire(durationMs + safetyMarginMs);
+				future = scheduledExecutorService.schedule(this::renew,
+						durationMs, MILLISECONDS);
+				acquired = android.os.SystemClock.elapsedRealtime();
+			} else if (LOG.isLoggable(FINE)) {
+				LOG.fine("Wake lock " + tag + " has " + refCount + " holders");
+			}
+		}
+	}
+
+	private void renew() {
+		if (LOG.isLoggable(INFO)) LOG.info("Renewing wake lock " + tag);
+		synchronized (lock) {
+			if (wakeLock == null) {
+				LOG.info("Already released");
+				return;
+			}
+			if (LOG.isLoggable(FINE)) {
+				LOG.fine("Wake lock " + tag + " has " + refCount + " holders");
+			}
+			long now = android.os.SystemClock.elapsedRealtime();
+			long expiry = acquired + durationMs + safetyMarginMs;
+			if (now > expiry && LOG.isLoggable(WARNING)) {
+				LOG.warning("Wake lock expired " + (now - expiry) + " ms ago");
+			}
+			WakeLock oldWakeLock = wakeLock;
+			wakeLock = powerManager.newWakeLock(levelAndFlags, tag);
+			wakeLock.setReferenceCounted(false);
+			wakeLock.acquire(durationMs + safetyMarginMs);
+			oldWakeLock.release();
+			future = scheduledExecutorService.schedule(this::renew, durationMs,
+					MILLISECONDS);
+			acquired = now;
+		}
+	}
+
+	@Override
+	public void release() {
+		synchronized (lock) {
+			refCount--;
+			if (refCount == 0) {
+				if (LOG.isLoggable(INFO)) {
+					LOG.info("Releasing wake lock " + tag);
+				}
+				requireNonNull(future).cancel(false);
+				future = null;
+				requireNonNull(wakeLock).release();
+				wakeLock = null;
+				acquired = 0;
+			} else if (LOG.isLoggable(FINE)) {
+				LOG.fine("Wake lock " + tag + " has " + refCount + " holders");
+			}
+		}
+	}
+}
+
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/SharedWakeLock.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/SharedWakeLock.java
@@ -0,0 +1,22 @@
+package org.briarproject.bramble.system;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.system.AndroidWakeLock;
+
+@NotNullByDefault
+interface SharedWakeLock {
+
+	/**
+	 * Acquires the wake lock. This increments the wake lock's reference count,
+	 * so unlike {@link AndroidWakeLock#acquire()} every call to this method
+	 * must be followed by a balancing call to {@link #release()}.
+	 */
+	void acquire();
+
+	/**
+	 * Releases the wake lock. This decrements the wake lock's reference count,
+	 * so unlike {@link AndroidWakeLock#release()} every call to this method
+	 * must follow a balancing call to {@link #acquire()}.
+	 */
+	void release();
+}
--- a/bramble-android/src/main/java/org/briarproject/bramble/util/AndroidUtils.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/util/AndroidUtils.java
@@ -1,30 +1,42 @@
 package org.briarproject.bramble.util;

+import android.annotation.SuppressLint;
 import android.bluetooth.BluetoothAdapter;
 import android.content.Context;
 import android.os.Build;
 import android.provider.Settings;

+import org.briarproject.bramble.api.Pair;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
 import java.io.File;
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;

-import static android.content.Context.MODE_PRIVATE;
+import javax.annotation.Nullable;

+import static android.content.Context.MODE_PRIVATE;
+import static android.os.Build.VERSION.SDK_INT;
+import static java.util.Arrays.asList;
+import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+
+@NotNullByDefault
 public class AndroidUtils {

 	// Fake Bluetooth address returned by BluetoothAdapter on API 23 and later
 	private static final String FAKE_BLUETOOTH_ADDRESS = "02:00:00:00:00:00";

 	private static final String STORED_REPORTS = "dev-reports";
+	private static final String STORED_LOGCAT = "dev-logcat";

-	@SuppressWarnings("deprecation")
 	public static Collection<String> getSupportedArchitectures() {
 		List<String> abis = new ArrayList<>();
-		if (Build.VERSION.SDK_INT >= 21) {
-			abis.addAll(Arrays.asList(Build.SUPPORTED_ABIS));
+		if (SDK_INT >= 21) {
+			abis.addAll(asList(Build.SUPPORTED_ABIS));
 		} else {
 			abis.add(Build.CPU_ABI);
 			if (Build.CPU_ABI2 != null) abis.add(Build.CPU_ABI2);
@@ -34,37 +46,76 @@ public class AndroidUtils {

 	public static String getBluetoothAddress(Context ctx,
 			BluetoothAdapter adapter) {
+		return getBluetoothAddressAndMethod(ctx, adapter).getFirst();
+	}
+
+	public static Pair<String, String> getBluetoothAddressAndMethod(Context ctx,
+			BluetoothAdapter adapter) {
 		// Return the adapter's address if it's valid and not fake
+		@SuppressLint("HardwareIds")
 		String address = adapter.getAddress();
-		if (isValidBluetoothAddress(address)) return address;
+		if (isValidBluetoothAddress(address)) {
+			return new Pair<>(address, "adapter");
+		}
 		// Return the address from settings if it's valid and not fake
 		address = Settings.Secure.getString(ctx.getContentResolver(),
 				"bluetooth_address");
-		if (isValidBluetoothAddress(address)) return address;
+		if (isValidBluetoothAddress(address)) {
+			return new Pair<>(address, "settings");
+		}
+		// Try to get the address via reflection
+		address = getBluetoothAddressByReflection(adapter);
+		if (isValidBluetoothAddress(address)) {
+			return new Pair<>(requireNonNull(address), "reflection");
+		}
 		// Let the caller know we can't find the address
-		return "";
+		return new Pair<>("", "");
 	}

-	private static boolean isValidBluetoothAddress(String address) {
+	public static boolean isValidBluetoothAddress(@Nullable String address) {
 		return !StringUtils.isNullOrEmpty(address)
 				&& BluetoothAdapter.checkBluetoothAddress(address)
 				&& !address.equals(FAKE_BLUETOOTH_ADDRESS);
 	}

-	public static void deleteAppData(Context ctx) {
-		File dataDir = new File(ctx.getApplicationInfo().dataDir);
-		File[] children = dataDir.listFiles();
-		if (children != null) {
-			for (File child : children) {
-				if (!child.getName().equals("lib"))
-					IoUtils.deleteFileOrDir(child);
-			}
+	@Nullable
+	private static String getBluetoothAddressByReflection(
+			BluetoothAdapter adapter) {
+		try {
+			Field mServiceField =
+					adapter.getClass().getDeclaredField("mService");
+			mServiceField.setAccessible(true);
+			Object mService = mServiceField.get(adapter);
+			// mService may be null when Bluetooth is disabled
+			if (mService == null) throw new NoSuchFieldException();
+			Method getAddressMethod =
+					mService.getClass().getMethod("getAddress");
+			return (String) getAddressMethod.invoke(mService);
+		} catch (NoSuchFieldException e) {
+			return null;
+		} catch (IllegalAccessException e) {
+			return null;
+		} catch (NoSuchMethodException e) {
+			return null;
+		} catch (InvocationTargetException e) {
+			return null;
+		} catch (SecurityException e) {
+			return null;
 		}
-		// Recreate the cache dir as some OpenGL drivers expect it to exist
-		new File(dataDir, "cache").mkdir();
 	}

 	public static File getReportDir(Context ctx) {
 		return ctx.getDir(STORED_REPORTS, MODE_PRIVATE);
 	}
+
+	public static File getLogcatFile(Context ctx) {
+		return new File(ctx.getFilesDir(), STORED_LOGCAT);
+	}
+
+	/**
+	 * Returns an array of supported content types for image attachments.
+	 */
+	public static String[] getSupportedImageContentTypes() {
+		return new String[] {"image/jpeg", "image/png", "image/gif"};
+	}
 }
--- a/bramble-android/src/test/java/org/briarproject/bramble/account/AndroidAccountManagerTest.java
+++ b/bramble-android/src/test/java/org/briarproject/bramble/account/AndroidAccountManagerTest.java
@@ -0,0 +1,151 @@
+package org.briarproject.bramble.account;
+
+import android.app.Application;
+import android.content.SharedPreferences;
+import android.content.pm.ApplicationInfo;
+
+import org.briarproject.bramble.api.crypto.CryptoComponent;
+import org.briarproject.bramble.api.db.DatabaseConfig;
+import org.briarproject.bramble.api.identity.IdentityManager;
+import org.briarproject.bramble.test.BrambleMockTestCase;
+import org.jmock.Expectations;
+import org.jmock.lib.legacy.ClassImposteriser;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.File;
+
+import static junit.framework.Assert.assertFalse;
+import static junit.framework.Assert.assertTrue;
+import static org.briarproject.bramble.test.TestUtils.deleteTestDirectory;
+import static org.briarproject.bramble.test.TestUtils.getTestDirectory;
+
+public class AndroidAccountManagerTest extends BrambleMockTestCase {
+
+	private final SharedPreferences prefs =
+			context.mock(SharedPreferences.class, "prefs");
+	private final SharedPreferences defaultPrefs =
+			context.mock(SharedPreferences.class, "defaultPrefs");
+	private final DatabaseConfig databaseConfig =
+			context.mock(DatabaseConfig.class);
+	private final CryptoComponent crypto = context.mock(CryptoComponent.class);
+	private final IdentityManager identityManager =
+			context.mock(IdentityManager.class);
+	private final SharedPreferences.Editor
+			editor = context.mock(SharedPreferences.Editor.class);
+	private final Application app;
+	private final ApplicationInfo applicationInfo;
+
+	private final File testDir = getTestDirectory();
+	private final File keyDir = new File(testDir, "key");
+	private final File dbDir = new File(testDir, "db");
+
+	private AndroidAccountManager accountManager;
+
+	public AndroidAccountManagerTest() {
+		context.setImposteriser(ClassImposteriser.INSTANCE);
+		app = context.mock(Application.class);
+		applicationInfo = new ApplicationInfo();
+		applicationInfo.dataDir = testDir.getAbsolutePath();
+	}
+
+	@Before
+	public void setUp() {
+		context.checking(new Expectations() {{
+			allowing(databaseConfig).getDatabaseDirectory();
+			will(returnValue(dbDir));
+			allowing(databaseConfig).getDatabaseKeyDirectory();
+			will(returnValue(keyDir));
+			allowing(app).getApplicationContext();
+			will(returnValue(app));
+		}});
+		accountManager = new AndroidAccountManager(databaseConfig, crypto,
+				identityManager, prefs, app) {
+			@Override
+			SharedPreferences getDefaultSharedPreferences() {
+				return defaultPrefs;
+			}
+		};
+	}
+
+	@Test
+	public void testDeleteAccountClearsSharedPrefsAndDeletesFiles()
+			throws Exception {
+		// Directories 'code_cache', 'lib' and 'shared_prefs' should be spared
+		File codeCacheDir = new File(testDir, "code_cache");
+		File codeCacheFile = new File(codeCacheDir, "file");
+		File libDir = new File(testDir, "lib");
+		File libFile = new File(libDir, "file");
+		File sharedPrefsDir = new File(testDir, "shared_prefs");
+		File sharedPrefsFile = new File(sharedPrefsDir, "file");
+		// Directory 'cache' should be emptied
+		File cacheDir = new File(testDir, "cache");
+		File cacheFile = new File(cacheDir, "file");
+		// Other directories should be deleted
+		File potatoDir = new File(testDir, ".potato");
+		File potatoFile = new File(potatoDir, "file");
+		File filesDir = new File(testDir, "filesDir");
+		File externalCacheDir = new File(testDir, "externalCacheDir");
+
+		context.checking(new Expectations() {{
+			oneOf(prefs).edit();
+			will(returnValue(editor));
+			oneOf(editor).clear();
+			will(returnValue(editor));
+			oneOf(editor).commit();
+			will(returnValue(true));
+			oneOf(defaultPrefs).edit();
+			will(returnValue(editor));
+			oneOf(editor).clear();
+			will(returnValue(editor));
+			oneOf(editor).commit();
+			will(returnValue(true));
+			allowing(app).getApplicationInfo();
+			will(returnValue(applicationInfo));
+			oneOf(app).getFilesDir();
+			will(returnValue(filesDir));
+			oneOf(app).getCacheDir();
+			will(returnValue(cacheDir));
+			oneOf(app).getExternalCacheDir();
+			will(returnValue(externalCacheDir));
+		}});
+
+		assertTrue(dbDir.mkdirs());
+		assertTrue(keyDir.mkdirs());
+		assertTrue(codeCacheDir.mkdirs());
+		assertTrue(codeCacheFile.createNewFile());
+		assertTrue(libDir.mkdirs());
+		assertTrue(libFile.createNewFile());
+		assertTrue(sharedPrefsDir.mkdirs());
+		assertTrue(sharedPrefsFile.createNewFile());
+		assertTrue(cacheDir.mkdirs());
+		assertTrue(cacheFile.createNewFile());
+		assertTrue(potatoDir.mkdirs());
+		assertTrue(potatoFile.createNewFile());
+		assertTrue(filesDir.mkdirs());
+		assertTrue(externalCacheDir.mkdirs());
+
+		accountManager.deleteAccount();
+
+		assertFalse(dbDir.exists());
+		assertFalse(keyDir.exists());
+		assertTrue(codeCacheDir.exists());
+		assertTrue(codeCacheFile.exists());
+		assertTrue(libDir.exists());
+		assertTrue(libFile.exists());
+		assertTrue(sharedPrefsDir.exists());
+		assertTrue(sharedPrefsFile.exists());
+		assertTrue(cacheDir.exists());
+		assertFalse(cacheFile.exists());
+		assertFalse(potatoDir.exists());
+		assertFalse(potatoFile.exists());
+		assertFalse(filesDir.exists());
+		assertFalse(externalCacheDir.exists());
+	}
+
+	@After
+	public void tearDown() {
+		deleteTestDirectory(testDir);
+	}
+}
--- a/bramble-android/witness.gradle
+++ b/bramble-android/witness.gradle
@@ -0,0 +1,110 @@
+dependencyVerification {
+    verify = [
+        'cglib:cglib:3.2.0:cglib-3.2.0.jar:adb13bab79712ad6bdf1bd59f2a3918018a8016e722e8a357065afb9e6690861',
+        'com.android.tools.analytics-library:protos:27.1.1:protos-27.1.1.jar:13f77e73762e58ab372d140b3a6be6903aea9775b62dd14fbc62d4cc7069c9a4',
+        'com.android.tools.analytics-library:shared:27.1.1:shared-27.1.1.jar:82930a52001410e97d809930b670f4de3002286975f046b9de5f6b777b06d366',
+        'com.android.tools.analytics-library:tracker:27.1.1:tracker-27.1.1.jar:31bc5a00be0055bac89c9b2f34751883e987cd89e3ac1783720645c164f591d9',
+        'com.android.tools.build:aapt2-proto:4.1.0-alpha01-6193524:aapt2-proto-4.1.0-alpha01-6193524.jar:17e75523e1e92dd4f222c7368ee41df9e964a508232f591e265d0c499baf9dca',
+        'com.android.tools.build:apksig:4.1.1:apksig-4.1.1.jar:e0a69da9e5a03986d608b45bbf954ef0e6a0b3f58c1b8315bd169ec08b279e72',
+        'com.android.tools.build:apkzlib:4.1.1:apkzlib-4.1.1.jar:ba4b5e419b6be0130eae7f8301c3a551ad3976f487d2e0c6852ebb175ac41127',
+        'com.android.tools.build:builder-model:4.1.1:builder-model-4.1.1.jar:e95c99cc298ad67b8deb6ced99c51abc8f59afebedad044b1a10dde14646a4dd',
+        'com.android.tools.build:builder-test-api:4.1.1:builder-test-api-4.1.1.jar:464f596ab261c051c3847406748e843770dea123f6fa5fee8a9390644e709b7a',
+        'com.android.tools.build:builder:4.1.1:builder-4.1.1.jar:0f78d4759d2f7b57b95865522ec34596ba419b9982f3b25e3449213f9c98b80d',
+        'com.android.tools.build:gradle-api:4.1.1:gradle-api-4.1.1.jar:d42e6b539e4c1353ad3546e75ec8ce11a017b97481023e8ea18577eefe374358',
+        'com.android.tools.build:manifest-merger:27.1.1:manifest-merger-27.1.1.jar:7a45fa143687859bb2e5a961dcf6ee88094d3853de0cb543dc03dbcb0f4b554b',
+        'com.android.tools.ddms:ddmlib:27.1.1:ddmlib-27.1.1.jar:da6e4bd834b6a85dae8019039849d8bd96933347dfbf460df74913ddade6e40a',
+        'com.android.tools.external.com-intellij:intellij-core:27.1.1:intellij-core-27.1.1.jar:2591a7363c4443c59bf9f793730acafce9d6ec3076e2f46716edaf53a41b6fb6',
+        'com.android.tools.external.com-intellij:kotlin-compiler:27.1.1:kotlin-compiler-27.1.1.jar:5054ae770ba788f110303c65abd6b1fa28eccf52dee1274510e201b2b81885c8',
+        'com.android.tools.external.org-jetbrains:uast:27.1.1:uast-27.1.1.jar:54cd8f6886a9d2f5641659dd5c91f626629672cd48301f7f0bd6aad9bd448714',
+        'com.android.tools.layoutlib:layoutlib-api:27.1.1:layoutlib-api-27.1.1.jar:8a9a22e3b309521ea83b724e5a89cfdac6076f52d675c0e17d77b05527bc0f8c',
+        'com.android.tools.lint:lint-api:27.1.1:lint-api-27.1.1.jar:c1d8176094cb0478786070d40533efb578ebc53529a82f6ef5bee879bdca418b',
+        'com.android.tools.lint:lint-checks:27.1.1:lint-checks-27.1.1.jar:3899c91e00bd059b40c31a9ca00cd0f8303191947608735ae1b657323693fb61',
+        'com.android.tools.lint:lint-gradle-api:27.1.1:lint-gradle-api-27.1.1.jar:26aa89d38b9825cc73229daa82a68875801c8b8491f30497ce62aff1f206eb0d',
+        'com.android.tools.lint:lint-gradle:27.1.1:lint-gradle-27.1.1.jar:f7355823ead869f4d28184ba28b7a0c693b507519a2d3705bb9848a0f35b3756',
+        'com.android.tools.lint:lint-model:27.1.1:lint-model-27.1.1.jar:bc23c0c413bdfca59dac2cd56b870d8360d009e9ec0d365e71f774bcf127971d',
+        'com.android.tools.lint:lint:27.1.1:lint-27.1.1.jar:2f6038a5398a42bd591883c3f5e5894f4ec52ca1c3683bf94fa8553c1700af81',
+        'com.android.tools:annotations:27.1.1:annotations-27.1.1.jar:ff28c504d2acb9fd1a5ffbd97ae85cf59ee18c76927525aad250509bccf2cab1',
+        'com.android.tools:common:27.1.1:common-27.1.1.jar:63d9a2a9ad6d278db319f3749b9f50bdf5457ef7020074a1bebe124e714b535c',
+        'com.android.tools:dvlib:27.1.1:dvlib-27.1.1.jar:998a54201fc1cefee5f2399215e95c42b1f64f9e1d8f4452eb8255c68ba5440f',
+        'com.android.tools:repository:27.1.1:repository-27.1.1.jar:d25b74ccabf4d876903efb375e9af6fb380d8ae0445bb74bbdcc225c1e37fa1d',
+        'com.android.tools:sdk-common:27.1.1:sdk-common-27.1.1.jar:4473ae97d0ef7061ee1de61041d5aa97405ae08e44c09cf7bb278b42e4b97c7c',
+        'com.android.tools:sdklib:27.1.1:sdklib-27.1.1.jar:08e6b83961ac9724b3c1e3d0eff971f13be6701292c77914b8794480f3391250',
+        'com.android:signflinger:4.1.1:signflinger-4.1.1.jar:0c66825988873ec2d51057fa463f54a8f18fc7326ff4530b9da363b71e97ce60',
+        'com.android:zipflinger:4.1.1:zipflinger-4.1.1.jar:0a8c3e52ac13dd031236f9fb5ba4408b1d5dcd12325a05440b36da09d8881446',
+        'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
+        'com.google.code.gson:gson:2.8.5:gson-2.8.5.jar:233a0149fc365c9f6edbd683cfe266b19bdc773be98eabdaf6b3c924b48e7d81',
+        'com.google.dagger:dagger-compiler:2.24:dagger-compiler-2.24.jar:3c5afb955fb188da485cb2c048eff37dce0e1530b9780a0f2f7187d16d1ccc1f',
+        'com.google.dagger:dagger-producers:2.24:dagger-producers-2.24.jar:f10f45b95191954d5d6b043fca9e62fb621d21bf70634b8f8476c7988b504c3a',
+        'com.google.dagger:dagger-spi:2.24:dagger-spi-2.24.jar:c038445d14dbcb4054e61bf49e05009edf26fce4fdc7ec1a9db544784f68e718',
+        'com.google.dagger:dagger:2.24:dagger-2.24.jar:550a6e46a6dfcdf1d764887b6090cea94f783327e50e5c73754f18facfc70b64',
+        'com.google.errorprone:error_prone_annotations:2.2.0:error_prone_annotations-2.2.0.jar:6ebd22ca1b9d8ec06d41de8d64e0596981d9607b42035f9ed374f9de271a481a',
+        'com.google.errorprone:error_prone_annotations:2.3.2:error_prone_annotations-2.3.2.jar:357cd6cfb067c969226c442451502aee13800a24e950fdfde77bcdb4565a668d',
+        'com.google.errorprone:javac-shaded:9-dev-r4023-3:javac-shaded-9-dev-r4023-3.jar:65bfccf60986c47fbc17c9ebab0be626afc41741e0a6ec7109e0768817a36f30',
+        'com.google.googlejavaformat:google-java-format:1.5:google-java-format-1.5.jar:aa19ad7850fb85178aa22f2fddb163b84d6ce4d0035872f30d4408195ca1144e',
+        'com.google.guava:failureaccess:1.0.1:failureaccess-1.0.1.jar:a171ee4c734dd2da837e4b16be9df4661afab72a41adaf31eb84dfdaf936ca26',
+        'com.google.guava:guava:27.1-jre:guava-27.1-jre.jar:4a5aa70cc968a4d137e599ad37553e5cfeed2265e8c193476d7119036c536fe7',
+        'com.google.guava:guava:28.1-jre:guava-28.1-jre.jar:30beb8b8527bd07c6e747e77f1a92122c2f29d57ce347461a4a55eb26e382da4',
+        'com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava:listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar:b372a037d4230aa57fbeffdef30fd6123f9c0c2db85d0aced00c91b974f33f99',
+        'com.google.j2objc:j2objc-annotations:1.1:j2objc-annotations-1.1.jar:2994a7eb78f2710bd3d3bfb639b2c94e219cedac0d4d084d516e78c16dddecf6',
+        'com.google.j2objc:j2objc-annotations:1.3:j2objc-annotations-1.3.jar:21af30c92267bd6122c0e0b4d20cccb6641a37eaf956c6540ec471d584e64a7b',
+        'com.google.jimfs:jimfs:1.1:jimfs-1.1.jar:c4828e28d7c0a930af9387510b3bada7daa5c04d7c25a75c7b8b081f1c257ddd',
+        'com.google.protobuf:protobuf-java:3.10.0:protobuf-java-3.10.0.jar:161d7d61a8cb3970891c299578702fd079646e032329d6c2cabf998d191437c9',
+        'com.googlecode.json-simple:json-simple:1.1:json-simple-1.1.jar:2d9484f4c649f708f47f9a479465fc729770ee65617dca3011836602264f6439',
+        'com.squareup:javapoet:1.11.1:javapoet-1.11.1.jar:9cbf2107be499ec6e95afd36b58e3ca122a24166cdd375732e51267d64058e90',
+        'com.squareup:javawriter:2.5.0:javawriter-2.5.0.jar:fcfb09fb0ea0aa97d3cfe7ea792398081348e468f126b3603cb3803f240197f0',
+        'com.sun.activation:javax.activation:1.2.0:javax.activation-1.2.0.jar:993302b16cd7056f21e779cc577d175a810bb4900ef73cd8fbf2b50f928ba9ce',
+        'com.sun.istack:istack-commons-runtime:3.0.7:istack-commons-runtime-3.0.7.jar:6443e10ba2e259fb821d9b6becf10db5316285fc30c53cec9d7b19a3877e7fdf',
+        'com.sun.xml.fastinfoset:FastInfoset:1.2.15:FastInfoset-1.2.15.jar:785861db11ca1bd0d1956682b974ad73eb19cd3e01a4b3fa82d62eca97210aec',
+        'commons-codec:commons-codec:1.10:commons-codec-1.10.jar:4241dfa94e711d435f29a4604a3e2de5c4aa3c165e23bd066be6fc1fc4309569',
+        'commons-logging:commons-logging:1.2:commons-logging-1.2.jar:daddea1ea0be0f56978ab3006b8ac92834afeefbd9b7e4e6316fca57df0fa636',
+        'it.unimi.dsi:fastutil:7.2.0:fastutil-7.2.0.jar:74fa208043740642f7e6eb09faba15965218ad2f50ce3020efb100136e4b591c',
+        'javax.activation:javax.activation-api:1.2.0:javax.activation-api-1.2.0.jar:43fdef0b5b6ceb31b0424b208b930c74ab58fac2ceeb7b3f6fd3aeb8b5ca4393',
+        'javax.annotation:jsr250-api:1.0:jsr250-api-1.0.jar:a1a922d0d9b6d183ed3800dfac01d1e1eb159f0e8c6f94736931c1def54a941f',
+        'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
+        'javax.xml.bind:jaxb-api:2.3.1:jaxb-api-2.3.1.jar:88b955a0df57880a26a74708bc34f74dcaf8ebf4e78843a28b50eae945732b06',
+        'junit:junit:4.12:junit-4.12.jar:59721f0805e223d84b90677887d9ff567dc534d7c502ca903c0c2b17f05c116a',
+        'net.ltgt.gradle.incap:incap:0.2:incap-0.2.jar:b625b9806b0f1e4bc7a2e3457119488de3cd57ea20feedd513db070a573a4ffd',
+        'net.sf.jopt-simple:jopt-simple:4.9:jopt-simple-4.9.jar:26c5856e954b5f864db76f13b86919b59c6eecf9fd930b96baa8884626baf2f5',
+        'net.sf.kxml:kxml2:2.3.0:kxml2-2.3.0.jar:f264dd9f79a1fde10ce5ecc53221eff24be4c9331c830b7d52f2f08a7b633de2',
+        'org.apache.ant:ant-launcher:1.9.4:ant-launcher-1.9.4.jar:7bccea20b41801ca17bcbc909a78c835d0f443f12d639c77bd6ae3d05861608d',
+        'org.apache.ant:ant:1.9.4:ant-1.9.4.jar:649ae0730251de07b8913f49286d46bba7b92d47c5f332610aa426c4f02161d8',
+        'org.apache.commons:commons-compress:1.12:commons-compress-1.12.jar:2c1542faf343185b7cab9c3d55c8ae5471d6d095d3887a4adefdbdf2984dc0b6',
+        'org.apache.httpcomponents:httpclient:4.5.6:httpclient-4.5.6.jar:c03f813195e7a80e3608d0ddd8da80b21696a4c92a6a2298865bf149071551c7',
+        'org.apache.httpcomponents:httpcore:4.4.10:httpcore-4.4.10.jar:78ba1096561957db1b55200a159b648876430342d15d461277e62360da19f6fd',
+        'org.apache.httpcomponents:httpmime:4.5.6:httpmime-4.5.6.jar:0b2b1102c18d3c7e05a77214b9b7501a6f6056174ae5604e0e256776eda7553e',
+        'org.beanshell:bsh:1.3.0:bsh-1.3.0.jar:9b04edc75d19db54f1b4e8b5355e9364384c6cf71eb0a1b9724c159d779879f8',
+        'org.bouncycastle:bcpkix-jdk15on:1.56:bcpkix-jdk15on-1.56.jar:7043dee4e9e7175e93e0b36f45b1ec1ecb893c5f755667e8b916eb8dd201c6ca',
+        'org.bouncycastle:bcprov-jdk15on:1.56:bcprov-jdk15on-1.56.jar:963e1ee14f808ffb99897d848ddcdb28fa91ddda867eb18d303e82728f878349',
+        'org.briarproject:obfs4proxy-android:0.0.12-dev-40245c4a:obfs4proxy-android-0.0.12-dev-40245c4a.zip:8ab05a8f8391be2cb5ab2b665c281a06d9e3a756bd0f95a40a36ca927866ea82',
+        'org.briarproject:tor-android:0.3.5.13:tor-android-0.3.5.13.zip:e0978db136731dae07774b722970cdae1e462fb5adc82845dd80a7e2d87f356c',
+        'org.checkerframework:checker-compat-qual:2.5.3:checker-compat-qual-2.5.3.jar:d76b9afea61c7c082908023f0cbc1427fab9abd2df915c8b8a3e7a509bccbc6d',
+        'org.checkerframework:checker-qual:2.5.2:checker-qual-2.5.2.jar:64b02691c8b9d4e7700f8ee2e742dce7ea2c6e81e662b7522c9ee3bf568c040a',
+        'org.checkerframework:checker-qual:2.8.1:checker-qual-2.8.1.jar:9103499008bcecd4e948da29b17864abb64304e15706444ae209d17ebe0575df',
+        'org.codehaus.groovy:groovy-all:2.4.15:groovy-all-2.4.15.jar:51d6c4e71782e85674239189499854359d380fb75e1a703756e3aaa5b98a5af0',
+        'org.codehaus.mojo:animal-sniffer-annotations:1.17:animal-sniffer-annotations-1.17.jar:92654f493ecfec52082e76354f0ebf87648dc3d5cec2e3c3cdb947c016747a53',
+        'org.codehaus.mojo:animal-sniffer-annotations:1.18:animal-sniffer-annotations-1.18.jar:47f05852b48ee9baefef80fa3d8cea60efa4753c0013121dd7fe5eef2e5c729d',
+        'org.glassfish.jaxb:jaxb-runtime:2.3.1:jaxb-runtime-2.3.1.jar:45fecfa5c8217ce1f3652ab95179790ec8cc0dec0384bca51cbeb94a293d9f2f',
+        'org.glassfish.jaxb:txw2:2.3.1:txw2-2.3.1.jar:34975dde1c6920f1a39791142235689bc3cd357e24d05edd8ff93b885bd68d60',
+        'org.hamcrest:hamcrest-core:1.3:hamcrest-core-1.3.jar:66fdef91e9739348df7a096aa384a5685f4e875584cce89386a7a47251c4d8e9',
+        'org.hamcrest:hamcrest-library:1.3:hamcrest-library-1.3.jar:711d64522f9ec410983bd310934296da134be4254a125080a0416ec178dfad1c',
+        'org.jetbrains.kotlin:kotlin-reflect:1.3.72:kotlin-reflect-1.3.72.jar:a188d9367de1c4ee9479db630985c0597b20709c83161b1430d24edb27e38c40',
+        'org.jetbrains.kotlin:kotlin-stdlib-common:1.3.72:kotlin-stdlib-common-1.3.72.jar:5e7d1552863e480c1628b1cc39ce230ef829f5b7230106215a05acda5172203a',
+        'org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.3.72:kotlin-stdlib-jdk7-1.3.72.jar:40566c0c08d414b9413ba556ff7f8a0b04b98b9f0f424d122dd2088510efccc4',
+        'org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.3.72:kotlin-stdlib-jdk8-1.3.72.jar:133da70cfc07b56094282eac5c59bccd59f167ee2ead22e5282876d8bc10bf95',
+        'org.jetbrains.kotlin:kotlin-stdlib:1.3.72:kotlin-stdlib-1.3.72.jar:3856a7349ebacd6d1be6802b2fed9c4dc2c5a564ea92b6b945ac988243d4b16b',
+        'org.jetbrains.trove4j:trove4j:20160824:trove4j-20160824.jar:1917871c8deb468307a584680c87a44572f5a8b0b98c6d397fc0f5f86596dbe7',
+        'org.jetbrains:annotations:13.0:annotations-13.0.jar:ace2a10dc8e2d5fd34925ecac03e4988b2c0f851650c94b8cef49ba1bd111478',
+        'org.jmock:jmock-junit4:2.8.2:jmock-junit4-2.8.2.jar:f7ee4df4f7bd7b7f1cafad3b99eb74d579f109d5992ff625347352edb55e674c',
+        'org.jmock:jmock-legacy:2.8.2:jmock-legacy-2.8.2.jar:f2b985a5c08a9edb7f37612330c058809da3f6a6d63ce792426ebf8ff0d6d31b',
+        'org.jmock:jmock-testjar:2.8.2:jmock-testjar-2.8.2.jar:8900860f72c474e027cf97fe78dcbf154a1aa7fc62b6845c5fb4e4f3c7bc8760',
+        'org.jmock:jmock:2.8.2:jmock-2.8.2.jar:6c73cb4a2e6dbfb61fd99c9a768539c170ab6568e57846bd60dbf19596b65b16',
+        'org.jvnet.staxex:stax-ex:1.8:stax-ex-1.8.jar:95b05d9590af4154c6513b9c5dc1fb2e55b539972ba0a9ef28e9a0c01d83ad77',
+        'org.objenesis:objenesis:2.1:objenesis-2.1.jar:c74330cc6b806c804fd37e74487b4fe5d7c2750c5e15fbc6efa13bdee1bdef80',
+        'org.ow2.asm:asm-analysis:7.0:asm-analysis-7.0.jar:e981f8f650c4d900bb033650b18e122fa6b161eadd5f88978d08751f72ee8474',
+        'org.ow2.asm:asm-commons:7.0:asm-commons-7.0.jar:fed348ef05958e3e846a3ac074a12af5f7936ef3d21ce44a62c4fa08a771927d',
+        'org.ow2.asm:asm-tree:7.0:asm-tree-7.0.jar:cfd7a0874f9de36a999c127feeadfbfe6e04d4a71ee954d7af3d853f0be48a6c',
+        'org.ow2.asm:asm-util:7.0:asm-util-7.0.jar:75fbbca440ef463f41c2b0ab1a80abe67e910ac486da60a7863cbcb5bae7e145',
+        'org.ow2.asm:asm:5.0.4:asm-5.0.4.jar:896618ed8ae62702521a78bc7be42b7c491a08e6920a15f89a3ecdec31e9a220',
+        'org.ow2.asm:asm:7.0:asm-7.0.jar:b88ef66468b3c978ad0c97fd6e90979e56155b4ac69089ba7a44e9aa7ffe9acf',
+    ]
+}
--- a/bramble-api/build.gradle
+++ b/bramble-api/build.gradle
@@ -1,31 +1,21 @@
-apply plugin: 'java'
-sourceCompatibility = 1.6
-targetCompatibility = 1.6
+apply plugin: 'java-library'
+sourceCompatibility = 1.8
+targetCompatibility = 1.8

+apply plugin: 'ru.vyarus.animalsniffer'
 apply plugin: 'witness'
+apply from: 'witness.gradle'

 dependencies {
-	compile "com.google.dagger:dagger:2.0.2"
-	compile 'com.google.dagger:dagger-compiler:2.0.2'
-	compile 'com.google.code.findbugs:jsr305:3.0.2'
+	implementation "com.google.dagger:dagger:2.24"
+	implementation 'com.google.code.findbugs:jsr305:3.0.2'

-	testCompile 'junit:junit:4.12'
-	testCompile "org.jmock:jmock:2.8.2"
-	testCompile "org.jmock:jmock-junit4:2.8.2"
-	testCompile "org.jmock:jmock-legacy:2.8.2"
-	testCompile "org.hamcrest:hamcrest-library:1.3"
-	testCompile "org.hamcrest:hamcrest-core:1.3"
-}
+	testImplementation 'junit:junit:4.12'
+	testImplementation "org.jmock:jmock:2.8.2"
+	testImplementation "org.jmock:jmock-junit4:2.8.2"
+	testImplementation "org.jmock:jmock-legacy:2.8.2"

-dependencyVerification {
-	verify = [
-			'com.google.dagger:dagger:84c0282ed8be73a29e0475d639da030b55dee72369e58dd35ae7d4fe6243dcf9',
-			'com.google.dagger:dagger-compiler:b74bc9de063dd4c6400b232231f2ef5056145b8fbecbf5382012007dd1c071b3',
-			'com.google.code.findbugs:jsr305:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
-			'javax.inject:javax.inject:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
-			'com.google.dagger:dagger-producers:99ec15e8a0507ba569e7655bc1165ee5e5ca5aa914b3c8f7e2c2458f724edd6b',
-			'com.google.guava:guava:d664fbfc03d2e5ce9cab2a44fb01f1d0bf9dfebeccc1a473b1f9ea31f79f6f99',
-	]
+	signature 'org.codehaus.mojo.signature:java16:1.1@signature'
 }

 // needed to make test output available to bramble-core and briar-core
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/Bytes.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/Bytes.java
@@ -4,8 +4,8 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.util.StringUtils;

 import java.util.Arrays;
-import java.util.Comparator;

+import javax.annotation.Nullable;
 import javax.annotation.concurrent.ThreadSafe;

 /**
@@ -15,8 +15,6 @@ import javax.annotation.concurrent.ThreadSafe;
@NotNullByDefault
 public class Bytes implements Comparable<Bytes> {

-	public static final BytesComparator COMPARATOR = new BytesComparator();
-
 	private final byte[] bytes;

 	private int hashCode = -1;
@@ -38,20 +36,13 @@ public class Bytes implements Comparable<Bytes> {
 	}

 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		return o instanceof Bytes && Arrays.equals(bytes, ((Bytes) o).bytes);
 	}

 	@Override
 	public int compareTo(Bytes other) {
-		byte[] aBytes = bytes, bBytes = other.bytes;
-		int length = Math.min(aBytes.length, bBytes.length);
-		for (int i = 0; i < length; i++) {
-			int aUnsigned = aBytes[i] & 0xFF, bUnsigned = bBytes[i] & 0xFF;
-			if (aUnsigned < bUnsigned) return -1;
-			if (aUnsigned > bUnsigned) return 1;
-		}
-		return aBytes.length - bBytes.length;
+		return compare(bytes, other.bytes);
 	}

 	@Override
@@ -60,11 +51,13 @@ public class Bytes implements Comparable<Bytes> {
 				"(" + StringUtils.toHexString(getBytes()) + ")";
 	}

-	public static class BytesComparator implements Comparator<Bytes> {
-
-		@Override
-		public int compare(Bytes a, Bytes b) {
-			return a.compareTo(b);
+	public static int compare(byte[] a, byte[] b) {
+		int length = Math.min(a.length, b.length);
+		for (int i = 0; i < length; i++) {
+			int aUnsigned = a[i] & 0xFF, bUnsigned = b[i] & 0xFF;
+			if (aUnsigned < bUnsigned) return -1;
+			if (aUnsigned > bUnsigned) return 1;
 		}
+		return a.length - b.length;
 	}
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/FeatureFlags.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/FeatureFlags.java
@@ -0,0 +1,12 @@
+package org.briarproject.bramble.api;
+
+/**
+ * Interface for specifying which features are enabled in a build.
+ */
+public interface FeatureFlags {
+
+	boolean shouldEnableImageAttachments();
+
+	boolean shouldEnableProfilePictures();
+
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/Multiset.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/Multiset.java
@@ -0,0 +1,101 @@
+package org.briarproject.bramble.api;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.NoSuchElementException;
+import java.util.Set;
+
+import javax.annotation.concurrent.NotThreadSafe;
+
+@NotThreadSafe
+@NotNullByDefault
+public class Multiset<T> {
+
+	private final Map<T, Integer> map = new HashMap<>();
+
+	private int total = 0;
+
+	/**
+	 * Returns how many items the multiset contains in total.
+	 */
+	public int getTotal() {
+		return total;
+	}
+
+	/**
+	 * Returns how many unique items the multiset contains.
+	 */
+	public int getUnique() {
+		return map.size();
+	}
+
+	/**
+	 * Returns how many of the given item the multiset contains.
+	 */
+	public int getCount(T t) {
+		Integer count = map.get(t);
+		return count == null ? 0 : count;
+	}
+
+	/**
+	 * Adds the given item to the multiset and returns how many of the item
+	 * the multiset now contains.
+	 */
+	public int add(T t) {
+		Integer count = map.get(t);
+		if (count == null) count = 0;
+		map.put(t, count + 1);
+		total++;
+		return count + 1;
+	}
+
+	/**
+	 * Removes the given item from the multiset and returns how many of the
+	 * item the multiset now contains.
+	 * @throws NoSuchElementException if the item is not in the multiset.
+	 */
+	public int remove(T t) {
+		Integer count = map.get(t);
+		if (count == null) throw new NoSuchElementException();
+		if (count == 1) map.remove(t);
+		else map.put(t, count - 1);
+		total--;
+		return count - 1;
+	}
+
+	/**
+	 * Removes all occurrences of the given item from the multiset.
+	 */
+	public int removeAll(T t) {
+		Integer count = map.remove(t);
+		if (count == null) return 0;
+		total -= count;
+		return count;
+	}
+
+	/**
+	 * Returns true if the multiset contains any occurrences of the given item.
+	 */
+	public boolean contains(T t) {
+		return map.containsKey(t);
+	}
+
+	/**
+	 * Removes all items from the multiset.
+	 */
+	public void clear() {
+		map.clear();
+		total = 0;
+	}
+
+	/**
+	 * Returns the set of unique items the multiset contains. The returned set
+	 * is unmodifiable.
+	 */
+	public Set<T> keySet() {
+		return Collections.unmodifiableSet(map.keySet());
+	}
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/Nameable.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/Nameable.java
@@ -0,0 +1,10 @@
+package org.briarproject.bramble.api;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface Nameable {
+
+	String getName();
+
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/Pair.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/Pair.java
@@ -0,0 +1,26 @@
+package org.briarproject.bramble.api;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.concurrent.Immutable;
+
+@Immutable
+@NotNullByDefault
+public class Pair<A, B> {
+
+	private final A first;
+	private final B second;
+
+	public Pair(A first, B second) {
+		this.first = first;
+		this.second = second;
+	}
+
+	public A getFirst() {
+		return first;
+	}
+
+	public B getSecond() {
+		return second;
+	}
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/Predicate.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/Predicate.java
@@ -0,0 +1,9 @@
+package org.briarproject.bramble.api;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface Predicate<T> {
+
+	boolean test(T t);
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/StringMap.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/StringMap.java
@@ -38,4 +38,18 @@ public abstract class StringMap extends Hashtable<String, String> {
 	public void putInt(String key, int value) {
 		put(key, String.valueOf(value));
 	}
+
+	public long getLong(String key, long defaultValue) {
+		String s = get(key);
+		if (s == null) return defaultValue;
+		try {
+			return Long.valueOf(s);
+		} catch (NumberFormatException e) {
+			return defaultValue;
+		}
+	}
+
+	public void putLong(String key, long value) {
+		put(key, String.valueOf(value));
+	}
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/UnsupportedVersionException.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/UnsupportedVersionException.java
@@ -0,0 +1,18 @@
+package org.briarproject.bramble.api;
+
+/**
+ * Thrown when data being parsed uses a protocol or format version that is not
+ * supported.
+ */
+public class UnsupportedVersionException extends FormatException {
+
+	private final boolean tooOld;
+
+	public UnsupportedVersionException(boolean tooOld) {
+		this.tooOld = tooOld;
+	}
+
+	public boolean isTooOld() {
+		return tooOld;
+	}
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/account/AccountManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/account/AccountManager.java
@@ -0,0 +1,71 @@
+package org.briarproject.bramble.api.account;
+
+import org.briarproject.bramble.api.crypto.DecryptionException;
+import org.briarproject.bramble.api.crypto.SecretKey;
+import org.briarproject.bramble.api.identity.IdentityManager;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.Nullable;
+
+@NotNullByDefault
+public interface AccountManager {
+
+	/**
+	 * Returns true if the manager has the database key. This will be false
+	 * before {@link #createAccount(String, String)} or {@link #signIn(String)}
+	 * has been called, and true after {@link #createAccount(String, String)}
+	 * or {@link #signIn(String)} has returned true, until
+	 * {@link #deleteAccount()} is called or the process exits.
+	 */
+	boolean hasDatabaseKey();
+
+	/**
+	 * Returns the database key if the manager has it. This will be null
+	 * before {@link #createAccount(String, String)} or {@link #signIn(String)}
+	 * has been called, and non-null after
+	 * {@link #createAccount(String, String)} or {@link #signIn(String)} has
+	 * returned true, until {@link #deleteAccount()} is called or the process
+	 * exits.
+	 */
+	@Nullable
+	SecretKey getDatabaseKey();
+
+	/**
+	 * Returns true if the encrypted database key can be loaded from disk.
+	 */
+	boolean accountExists();
+
+	/**
+	 * Creates an identity with the given name and registers it with the
+	 * {@link IdentityManager}. Creates a database key, encrypts it with the
+	 * given password and stores it on disk. {@link #accountExists()} will
+	 * return true after this method returns true.
+	 */
+	boolean createAccount(String name, String password);
+
+	/**
+	 * Deletes all account state from disk. {@link #accountExists()} will
+	 * return false after this method returns.
+	 */
+	void deleteAccount();
+
+	/**
+	 * Loads the encrypted database key from disk and decrypts it with the
+	 * given password.
+	 *
+	 * @throws DecryptionException If the database key could not be loaded and
+	 * decrypted.
+	 */
+	void signIn(String password) throws DecryptionException;
+
+	/**
+	 * Loads the encrypted database key from disk, decrypts it with the old
+	 * password, encrypts it with the new password, and stores it on disk,
+	 * replacing the old key.
+	 *
+	 * @throws DecryptionException If the database key could not be loaded and
+	 * decrypted.
+	 */
+	void changePassword(String oldPassword, String newPassword)
+			throws DecryptionException;
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/battery/BatteryManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/battery/BatteryManager.java
@@ -0,0 +1,6 @@
+package org.briarproject.bramble.api.battery;
+
+public interface BatteryManager {
+
+	boolean isCharging();
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/battery/event/BatteryEvent.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/battery/event/BatteryEvent.java
@@ -0,0 +1,19 @@
+package org.briarproject.bramble.api.battery.event;
+
+import org.briarproject.bramble.api.event.Event;
+
+/**
+ * An event that is broadcast when the device starts or stops charging.
+ */
+public class BatteryEvent extends Event {
+
+	private final boolean charging;
+
+	public BatteryEvent(boolean charging) {
+		this.charging = charging;
+	}
+
+	public boolean isCharging() {
+		return charging;
+	}
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfIncomingMessageHook.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfIncomingMessageHook.java
@@ -1,7 +1,6 @@
-package org.briarproject.briar.client;
+package org.briarproject.bramble.api.client;

 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.client.ClientHelper;
 import org.briarproject.bramble.api.data.BdfDictionary;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.MetadataParser;
@@ -12,19 +11,13 @@ import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.InvalidMessageException;
 import org.briarproject.bramble.api.sync.Message;
-import org.briarproject.bramble.api.sync.ValidationManager.IncomingMessageHook;
-import org.briarproject.briar.api.client.MessageQueueManager.IncomingQueueMessageHook;
-import org.briarproject.briar.api.client.QueueMessage;
+import org.briarproject.bramble.api.sync.validation.IncomingMessageHook;

 import javax.annotation.concurrent.Immutable;

-import static org.briarproject.bramble.api.sync.SyncConstants.MESSAGE_HEADER_LENGTH;
-import static org.briarproject.briar.api.client.QueueMessage.QUEUE_MESSAGE_HEADER_LENGTH;
-
@Immutable
@NotNullByDefault
-public abstract class BdfIncomingMessageHook implements IncomingMessageHook,
-		IncomingQueueMessageHook {
+public abstract class BdfIncomingMessageHook implements IncomingMessageHook {

 	protected final DatabaseComponent db;
 	protected final ClientHelper clientHelper;
@@ -40,6 +33,8 @@ public abstract class BdfIncomingMessageHook implements IncomingMessageHook,
 	/**
 	 * Called once for each incoming message that passes validation.
 	 *
+	 * @param txn A read-write transaction
+	 * @return Whether or not this message should be shared
 	 * @throws DbException Should only be used for real database errors.
 	 * If this is thrown, delivery will be attempted again at next startup,
 	 * whereas if a FormatException is thrown, the message will be permanently
@@ -60,29 +55,11 @@ public abstract class BdfIncomingMessageHook implements IncomingMessageHook,
 	public boolean incomingMessage(Transaction txn, Message m, Metadata meta)
 			throws DbException, InvalidMessageException {
 		try {
-			return incomingMessage(txn, m, meta, MESSAGE_HEADER_LENGTH);
+			BdfList body = clientHelper.toList(m);
+			BdfDictionary metaDictionary = metadataParser.parse(meta);
+			return incomingMessage(txn, m, body, metaDictionary);
 		} catch (FormatException e) {
 			throw new InvalidMessageException(e);
 		}
 	}
-
-	@Override
-	public void incomingMessage(Transaction txn, QueueMessage q, Metadata meta)
-			throws DbException, InvalidMessageException {
-		try {
-			incomingMessage(txn, q, meta, QUEUE_MESSAGE_HEADER_LENGTH);
-		} catch (FormatException e) {
-			throw new InvalidMessageException(e);
-		}
-	}
-
-	private boolean incomingMessage(Transaction txn, Message m, Metadata meta,
-			int headerLength) throws DbException, FormatException {
-		byte[] raw = m.getRaw();
-		BdfList body = clientHelper.toList(raw, headerLength,
-				raw.length - headerLength);
-		BdfDictionary metaDictionary = metadataParser.parse(meta);
-		return incomingMessage(txn, m, body, metaDictionary);
-	}
-
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfMessageContext.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfMessageContext.java
@@ -23,7 +23,7 @@ public class BdfMessageContext {
 	}

 	public BdfMessageContext(BdfDictionary dictionary) {
-		this(dictionary, Collections.<MessageId>emptyList());
+		this(dictionary, Collections.emptyList());
 	}

 	public BdfDictionary getDictionary() {
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfMessageValidator.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfMessageValidator.java
@@ -9,14 +9,13 @@ import org.briarproject.bramble.api.sync.Group;
 import org.briarproject.bramble.api.sync.InvalidMessageException;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageContext;
-import org.briarproject.bramble.api.sync.ValidationManager.MessageValidator;
+import org.briarproject.bramble.api.sync.validation.MessageValidator;
 import org.briarproject.bramble.api.system.Clock;

 import java.util.logging.Logger;

 import javax.annotation.concurrent.Immutable;

-import static org.briarproject.bramble.api.sync.SyncConstants.MESSAGE_HEADER_LENGTH;
 import static org.briarproject.bramble.api.transport.TransportConstants.MAX_CLOCK_DIFFERENCE;

@Immutable
@@ -49,14 +48,9 @@ public abstract class BdfMessageValidator implements MessageValidator {
 			throw new InvalidMessageException(
 					"Timestamp is too far in the future");
 		}
-		byte[] raw = m.getRaw();
-		if (raw.length <= MESSAGE_HEADER_LENGTH) {
-			throw new InvalidMessageException("Message is too short");
-		}
 		try {
-			BdfList body = clientHelper.toList(raw, MESSAGE_HEADER_LENGTH,
-					raw.length - MESSAGE_HEADER_LENGTH);
-			BdfMessageContext result = validateMessage(m, g, body);
+			BdfList bodyList = clientHelper.toList(m.getBody());
+			BdfMessageContext result = validateMessage(m, g, bodyList);
 			Metadata meta = metadataEncoder.encode(result.getDictionary());
 			return new MessageContext(meta, result.getDependencies());
 		} catch (FormatException e) {
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/client/ClientHelper.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/client/ClientHelper.java
@@ -1,11 +1,16 @@
 package org.briarproject.bramble.api.client;

 import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.crypto.PrivateKey;
+import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.data.BdfDictionary;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
+import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.TransportId;
+import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageId;
@@ -13,8 +18,6 @@ import org.briarproject.bramble.api.sync.MessageId;
 import java.security.GeneralSecurityException;
 import java.util.Map;

-import javax.annotation.Nullable;
-
@NotNullByDefault
 public interface ClientHelper {

@@ -22,23 +25,22 @@ public interface ClientHelper {
 			throws DbException, FormatException;

 	void addLocalMessage(Transaction txn, Message m, BdfDictionary metadata,
-			boolean shared) throws DbException, FormatException;
+			boolean shared, boolean temporary)
+			throws DbException, FormatException;
+
+	Message createMessage(GroupId g, long timestamp, byte[] body);

 	Message createMessage(GroupId g, long timestamp, BdfList body)
 			throws FormatException;

 	Message createMessageForStoringMetadata(GroupId g);

-	@Nullable
 	Message getMessage(MessageId m) throws DbException;

-	@Nullable
 	Message getMessage(Transaction txn, MessageId m) throws DbException;

-	@Nullable
 	BdfList getMessageAsList(MessageId m) throws DbException, FormatException;

-	@Nullable
 	BdfList getMessageAsList(Transaction txn, MessageId m) throws DbException,
 			FormatException;

@@ -87,16 +89,34 @@ public interface ClientHelper {
 	BdfDictionary toDictionary(byte[] b, int off, int len)
 			throws FormatException;

+	BdfDictionary toDictionary(TransportProperties transportProperties);
+
+	BdfDictionary toDictionary(Map<TransportId, TransportProperties> map);
+
 	BdfList toList(byte[] b, int off, int len) throws FormatException;

 	BdfList toList(byte[] b) throws FormatException;

 	BdfList toList(Message m) throws FormatException;

-	byte[] sign(String label, BdfList toSign, byte[] privateKey)
+	BdfList toList(Author a);
+
+	byte[] sign(String label, BdfList toSign, PrivateKey privateKey)
 			throws FormatException, GeneralSecurityException;

-	void verifySignature(String label, byte[] sig, byte[] publicKey,
-			BdfList signed) throws FormatException, GeneralSecurityException;
+	void verifySignature(byte[] signature, String label, BdfList signed,
+			PublicKey publicKey)
+			throws FormatException, GeneralSecurityException;
+
+	Author parseAndValidateAuthor(BdfList author) throws FormatException;
+
+	PublicKey parseAndValidateAgreementPublicKey(byte[] publicKeyBytes)
+			throws FormatException;
+
+	TransportProperties parseAndValidateTransportProperties(
+			BdfDictionary properties) throws FormatException;
+
+	Map<TransportId, TransportProperties> parseAndValidateTransportPropertiesMap(
+			BdfDictionary properties) throws FormatException;

 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/client/ContactGroupFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/client/ContactGroupFactory.java
@@ -12,18 +12,19 @@ public interface ContactGroupFactory {
 	/**
 	 * Creates a group that is not shared with any contacts.
 	 */
-	Group createLocalGroup(ClientId clientId);
+	Group createLocalGroup(ClientId clientId, int majorVersion);

 	/**
 	 * Creates a group for the given client to share with the given contact.
 	 */
-	Group createContactGroup(ClientId clientId, Contact contact);
+	Group createContactGroup(ClientId clientId, int majorVersion,
+			Contact contact);

 	/**
 	 * Creates a group for the given client to share between the given authors
 	 * identified by their AuthorIds.
 	 */
-	Group createContactGroup(ClientId clientId, AuthorId authorId1,
-			AuthorId authorId2);
+	Group createContactGroup(ClientId clientId, int majorVersion,
+			AuthorId authorId1, AuthorId authorId2);

 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/connection/ConnectionManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/connection/ConnectionManager.java
@@ -0,0 +1,49 @@
+package org.briarproject.bramble.api.connection;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.contact.PendingContactId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.TransportConnectionReader;
+import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
+import org.briarproject.bramble.api.plugin.TransportId;
+import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
+
+@NotNullByDefault
+public interface ConnectionManager {
+
+	/**
+	 * Manages an incoming connection from a contact over a simplex transport.
+	 */
+	void manageIncomingConnection(TransportId t, TransportConnectionReader r);
+
+	/**
+	 * Manages an incoming connection from a contact over a duplex transport.
+	 */
+	void manageIncomingConnection(TransportId t, DuplexTransportConnection d);
+
+	/**
+	 * Manages an incoming handshake connection from a pending contact over a
+	 * duplex transport.
+	 */
+	void manageIncomingConnection(PendingContactId p, TransportId t,
+			DuplexTransportConnection d);
+
+	/**
+	 * Manages an outgoing connection to a contact over a simplex transport.
+	 */
+	void manageOutgoingConnection(ContactId c, TransportId t,
+			TransportConnectionWriter w);
+
+	/**
+	 * Manages an outgoing connection to a contact over a duplex transport.
+	 */
+	void manageOutgoingConnection(ContactId c, TransportId t,
+			DuplexTransportConnection d);
+
+	/**
+	 * Manages an outgoing handshake connection to a pending contact over a
+	 * duplex transport.
+	 */
+	void manageOutgoingConnection(PendingContactId p, TransportId t,
+			DuplexTransportConnection d);
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/connection/ConnectionRegistry.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/connection/ConnectionRegistry.java
@@ -0,0 +1,130 @@
+package org.briarproject.bramble.api.connection;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.contact.PendingContactId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.PluginConfig;
+import org.briarproject.bramble.api.plugin.TransportId;
+import org.briarproject.bramble.api.plugin.event.ConnectionClosedEvent;
+import org.briarproject.bramble.api.plugin.event.ConnectionOpenedEvent;
+import org.briarproject.bramble.api.plugin.event.ContactConnectedEvent;
+import org.briarproject.bramble.api.plugin.event.ContactDisconnectedEvent;
+import org.briarproject.bramble.api.rendezvous.event.RendezvousConnectionClosedEvent;
+import org.briarproject.bramble.api.rendezvous.event.RendezvousConnectionOpenedEvent;
+import org.briarproject.bramble.api.sync.Priority;
+
+import java.util.Collection;
+
+/**
+ * Keeps track of which contacts are currently connected by which transports.
+ */
+@NotNullByDefault
+public interface ConnectionRegistry {
+
+	/**
+	 * Registers an incoming connection from the given contact over the given
+	 * transport. The connection's {@link Priority priority} can be set later
+	 * via {@link #setPriority(ContactId, TransportId, InterruptibleConnection,
+	 * Priority)} if a priority record is received from the contact.
+	 * <p>
+	 * Broadcasts {@link ConnectionOpenedEvent}. Also broadcasts
+	 * {@link ContactConnectedEvent} if this is the only connection with the
+	 * contact.
+	 */
+	void registerIncomingConnection(ContactId c, TransportId t,
+			InterruptibleConnection conn);
+
+	/**
+	 * Registers an outgoing connection to the given contact over the given
+	 * transport.
+	 * <p>
+	 * Broadcasts {@link ConnectionOpenedEvent}. Also broadcasts
+	 * {@link ContactConnectedEvent} if this is the only connection with the
+	 * contact.
+	 * <p>
+	 * If the registry has any "better" connections with the given contact, the
+	 * given connection will be interrupted. If the registry has any "worse"
+	 * connections with the given contact, those connections will be
+	 * interrupted.
+	 * <p>
+	 * Connection A is considered "better" than connection B if both
+	 * connections have had their priorities set, and either A's transport is
+	 * {@link PluginConfig#getTransportPreferences() preferred} to B's, or
+	 * they use the same transport and A has higher {@link Priority priority}
+	 * than B.
+	 * <p>
+	 * For backward compatibility, connections without priorities are not
+	 * considered better or worse than other connections.
+	 */
+	void registerOutgoingConnection(ContactId c, TransportId t,
+			InterruptibleConnection conn, Priority priority);
+
+	/**
+	 * Unregisters a connection with the given contact over the given transport.
+	 * <p>
+	 * Broadcasts {@link ConnectionClosedEvent}. Also broadcasts
+	 * {@link ContactDisconnectedEvent} if this is the only connection with
+	 * the contact.
+	 */
+	void unregisterConnection(ContactId c, TransportId t,
+			InterruptibleConnection conn, boolean incoming, boolean exception);
+
+	/**
+	 * Sets the {@link Priority priority} of a connection that was previously
+	 * registered via {@link #registerIncomingConnection(ContactId, TransportId,
+	 * InterruptibleConnection)}.
+	 * <p>
+	 * If the registry has any "better" connections with the given contact, the
+	 * given connection will be interrupted. If the registry has any "worse"
+	 * connections with the given contact, those connections will be
+	 * interrupted.
+	 * <p>
+	 * Connection A is considered "better" than connection B if both
+	 * connections have had their priorities set, and either A's transport is
+	 * {@link PluginConfig#getTransportPreferences() preferred} to B's, or
+	 * they use the same transport and A has higher {@link Priority priority}
+	 * than B.
+	 * <p>
+	 * For backward compatibility, connections without priorities are not
+	 * considered better or worse than other connections.
+	 */
+	void setPriority(ContactId c, TransportId t, InterruptibleConnection conn,
+			Priority priority);
+
+	/**
+	 * Returns any contacts that are connected via the given transport.
+	 */
+	Collection<ContactId> getConnectedContacts(TransportId t);
+
+	/**
+	 * Returns any contacts that are connected via the given transport or any
+	 * {@link PluginConfig#getTransportPreferences() better} transport.
+	 */
+	Collection<ContactId> getConnectedOrBetterContacts(TransportId t);
+
+	/**
+	 * Returns true if the given contact is connected via the given transport.
+	 */
+	boolean isConnected(ContactId c, TransportId t);
+
+	/**
+	 * Returns true if the given contact is connected via any transport.
+	 */
+	boolean isConnected(ContactId c);
+
+	/**
+	 * Registers a connection with the given pending contact. Broadcasts
+	 * {@link RendezvousConnectionOpenedEvent} if this is the only connection
+	 * with the pending contact.
+	 *
+	 * @return True if this is the only connection with the pending contact,
+	 * false if it is redundant and should be closed
+	 */
+	boolean registerConnection(PendingContactId p);
+
+	/**
+	 * Unregisters a connection with the given pending contact. Broadcasts
+	 * {@link RendezvousConnectionClosedEvent}.
+	 */
+	void unregisterConnection(PendingContactId p, boolean success);
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/connection/InterruptibleConnection.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/connection/InterruptibleConnection.java
@@ -0,0 +1,19 @@
+package org.briarproject.bramble.api.connection;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+/**
+ * A duplex sync connection that can be closed by interrupting its outgoing
+ * sync session.
+ */
+@NotNullByDefault
+public interface InterruptibleConnection {
+
+	/**
+	 * Interrupts the connection's outgoing sync session. If the underlying
+	 * transport connection is alive and the remote peer is cooperative, this
+	 * should result in both sync sessions ending and the connection being
+	 * cleanly closed.
+	 */
+	void interruptOutgoingSession();
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/Contact.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/Contact.java
@@ -1,11 +1,16 @@
 package org.briarproject.bramble.api.contact;

+import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;

+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;

+import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_AUTHOR_NAME_LENGTH;
+import static org.briarproject.bramble.util.StringUtils.toUtf8;
+
@Immutable
@NotNullByDefault
 public class Contact {
@@ -13,15 +18,26 @@ public class Contact {
 	private final ContactId id;
 	private final Author author;
 	private final AuthorId localAuthorId;
-	private final boolean verified, active;
+	@Nullable
+	private final String alias;
+	@Nullable
+	private final PublicKey handshakePublicKey;
+	private final boolean verified;

 	public Contact(ContactId id, Author author, AuthorId localAuthorId,
-			boolean verified, boolean active) {
+			@Nullable String alias, @Nullable PublicKey handshakePublicKey,
+			boolean verified) {
+		if (alias != null) {
+			int aliasLength = toUtf8(alias).length;
+			if (aliasLength == 0 || aliasLength > MAX_AUTHOR_NAME_LENGTH)
+				throw new IllegalArgumentException();
+		}
 		this.id = id;
 		this.author = author;
 		this.localAuthorId = localAuthorId;
+		this.alias = alias;
+		this.handshakePublicKey = handshakePublicKey;
 		this.verified = verified;
-		this.active = active;
 	}

 	public ContactId getId() {
@@ -36,12 +52,18 @@ public class Contact {
 		return localAuthorId;
 	}

-	public boolean isVerified() {
-		return verified;
+	@Nullable
+	public String getAlias() {
+		return alias;
 	}

-	public boolean isActive() {
-		return active;
+	@Nullable
+	public PublicKey getHandshakePublicKey() {
+		return handshakePublicKey;
+	}
+
+	public boolean isVerified() {
+		return verified;
 	}

 	@Override
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeListener.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeListener.java
@@ -1,20 +0,0 @@
-package org.briarproject.bramble.api.contact;
-
-import org.briarproject.bramble.api.identity.Author;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-
-@NotNullByDefault
-public interface ContactExchangeListener {
-
-	void contactExchangeSucceeded(Author remoteAuthor);
-
-	/**
-	 * The exchange failed because the contact already exists.
-	 */
-	void duplicateContact(Author remoteAuthor);
-
-	/**
-	 * A general failure.
-	 */
-	void contactExchangeFailed();
-}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeManager.java
@@ -0,0 +1,37 @@
+package org.briarproject.bramble.api.contact;
+
+import org.briarproject.bramble.api.crypto.SecretKey;
+import org.briarproject.bramble.api.db.ContactExistsException;
+import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
+
+import java.io.IOException;
+
+@NotNullByDefault
+public interface ContactExchangeManager {
+
+	/**
+	 * Exchanges contact information with a remote peer and adds the peer
+	 * as a contact.
+	 *
+	 * @param alice Whether the local peer takes the role of Alice
+	 * @return The newly added contact
+	 * @throws ContactExistsException If the contact already exists
+	 */
+	Contact exchangeContacts(DuplexTransportConnection conn,
+			SecretKey masterKey, boolean alice, boolean verified)
+			throws IOException, DbException;
+
+	/**
+	 * Exchanges contact information with a remote peer and adds the peer
+	 * as a contact, replacing the given pending contact.
+	 *
+	 * @param alice Whether the local peer takes the role of Alice
+	 * @return The newly added contact
+	 * @throws ContactExistsException If the contact already exists
+	 */
+	Contact exchangeContacts(PendingContactId p, DuplexTransportConnection conn,
+			SecretKey masterKey, boolean alice, boolean verified)
+			throws IOException, DbException;
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeTask.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeTask.java
@@ -1,22 +0,0 @@
-package org.briarproject.bramble.api.contact;
-
-import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.identity.LocalAuthor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.plugin.TransportId;
-import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
-
-/**
- * A task for conducting a contact information exchange with a remote peer.
- */
-@NotNullByDefault
-public interface ContactExchangeTask {
-
-	/**
-	 * Exchanges contact information with a remote peer.
-	 */
-	void startExchange(ContactExchangeListener listener,
-			LocalAuthor localAuthor, SecretKey masterSecret,
-			DuplexTransportConnection conn, TransportId transportId,
-			boolean alice);
-}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactId.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactId.java
@@ -2,11 +2,12 @@ package org.briarproject.bramble.api.contact;

 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;

+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;

 /**
 * Type-safe wrapper for an integer that uniquely identifies a contact within
- * the scope of a single node.
+ * the scope of the local device.
 */
@Immutable
@NotNullByDefault
@@ -28,7 +29,7 @@ public class ContactId {
 	}

 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		return o instanceof ContactId && id == ((ContactId) o).id;
 	}
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactManager.java
@@ -1,42 +1,149 @@
 package org.briarproject.bramble.api.contact;

+import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.Pair;
+import org.briarproject.bramble.api.UnsupportedVersionException;
 import org.briarproject.bramble.api.crypto.SecretKey;
+import org.briarproject.bramble.api.db.ContactExistsException;
 import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.db.NoSuchContactException;
+import org.briarproject.bramble.api.db.PendingContactExistsException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;

+import java.security.GeneralSecurityException;
 import java.util.Collection;

+import javax.annotation.Nullable;
+
@NotNullByDefault
 public interface ContactManager {

 	/**
-	 * Registers a hook to be called whenever a contact is added.
+	 * Registers a hook to be called whenever a contact is added or removed.
+	 * This method should be called before
+	 * {@link LifecycleManager#startServices(SecretKey)}.
 	 */
-	void registerAddContactHook(AddContactHook hook);
+	void registerContactHook(ContactHook hook);

 	/**
-	 * Registers a hook to be called whenever a contact is removed.
-	 */
-	void registerRemoveContactHook(RemoveContactHook hook);
-
-	/**
-	 * Stores a contact within the given transaction associated with the given
-	 * local and remote pseudonyms, and returns an ID for the contact.
+	 * Stores a contact associated with the given local and remote pseudonyms,
+	 * derives and stores rotation mode transport keys for each transport, and
+	 * returns an ID for the contact.
+	 *
+	 * @param rootKey The root key for a set of rotation mode transport keys
+	 * @param timestamp The timestamp for deriving rotation mode transport
+	 * keys from the root key
+	 * @param alice True if the local party is Alice
+	 * @param verified True if the contact's identity has been verified, which
+	 * is true if the contact was added in person or false if the contact was
+	 * introduced or added remotely
+	 * @param active True if the rotation mode transport keys can be used for
+	 * outgoing streams
 	 */
 	ContactId addContact(Transaction txn, Author remote, AuthorId local,
-			SecretKey master, long timestamp, boolean alice, boolean verified,
+			SecretKey rootKey, long timestamp, boolean alice, boolean verified,
 			boolean active) throws DbException;

 	/**
 	 * Stores a contact associated with the given local and remote pseudonyms,
-	 * and returns an ID for the contact.
+	 * replacing the given pending contact, derives and stores handshake mode
+	 * and rotation mode transport keys for each transport, and returns an ID
+	 * for the contact.
+	 *
+	 * @param rootKey The root key for a set of rotation mode transport keys
+	 * @param timestamp The timestamp for deriving rotation mode transport
+	 * keys from the root key
+	 * @param alice True if the local party is Alice
+	 * @param verified True if the contact's identity has been verified, which
+	 * is true if the contact was added in person or false if the contact was
+	 * introduced or added remotely
+	 * @param active True if the rotation mode transport keys can be used for
+	 * outgoing streams
+	 * @throws GeneralSecurityException If the pending contact's handshake
+	 * public key is invalid
 	 */
-	ContactId addContact(Author remote, AuthorId local,
-			SecretKey master, long timestamp, boolean alice, boolean verified,
-			boolean active) throws DbException;
+	ContactId addContact(Transaction txn, PendingContactId p, Author remote,
+			AuthorId local, SecretKey rootKey, long timestamp, boolean alice,
+			boolean verified, boolean active)
+			throws DbException, GeneralSecurityException;
+
+	/**
+	 * Stores a contact associated with the given local and remote pseudonyms
+	 * and returns an ID for the contact.
+	 *
+	 * @param verified True if the contact's identity has been verified, which
+	 * is true if the contact was added in person or false if the contact was
+	 * introduced or added remotely
+	 */
+	ContactId addContact(Transaction txn, Author remote, AuthorId local,
+			boolean verified) throws DbException;
+
+	/**
+	 * Stores a contact associated with the given local and remote pseudonyms,
+	 * derives and stores rotation mode transport keys for each transport, and
+	 * returns an ID for the contact.
+	 *
+	 * @param rootKey The root key for a set of rotation mode transport keys
+	 * @param timestamp The timestamp for deriving rotation mode transport
+	 * keys from the root key
+	 * @param alice True if the local party is Alice
+	 * @param verified True if the contact's identity has been verified, which
+	 * is true if the contact was added in person or false if the contact was
+	 * introduced or added remotely
+	 * @param active True if the rotation mode transport keys can be used for
+	 * outgoing streams
+	 */
+	ContactId addContact(Author remote, AuthorId local, SecretKey rootKey,
+			long timestamp, boolean alice, boolean verified, boolean active)
+			throws DbException;
+
+	/**
+	 * Returns the handshake link that needs to be sent to a contact we want
+	 * to add.
+	 */
+	String getHandshakeLink() throws DbException;
+
+	/**
+	 * Creates a {@link PendingContact} from the given handshake link and
+	 * alias, adds it to the database and returns it.
+	 *
+	 * @param link The handshake link received from the pending contact
+	 * @param alias The alias the user has given this pending contact
+	 * @throws UnsupportedVersionException If the link uses a format version
+	 * that is not supported
+	 * @throws FormatException If the link is invalid
+	 * @throws GeneralSecurityException If the pending contact's handshake
+	 * public key is invalid
+	 * @throws ContactExistsException If a contact with the same handshake
+	 * public key already exists
+	 * @throws PendingContactExistsException If a pending contact with the same
+	 * handshake public key already exists
+	 */
+	PendingContact addPendingContact(String link, String alias)
+			throws DbException, FormatException, GeneralSecurityException,
+			ContactExistsException, PendingContactExistsException;
+
+	/**
+	 * Returns the pending contact with the given ID.
+	 */
+	PendingContact getPendingContact(Transaction txn, PendingContactId p)
+			throws DbException;
+
+	/**
+	 * Returns a list of {@link PendingContact PendingContacts} and their
+	 * {@link PendingContactState states}.
+	 */
+	Collection<Pair<PendingContact, PendingContactState>> getPendingContacts()
+			throws DbException;
+
+	/**
+	 * Removes a {@link PendingContact}.
+	 */
+	void removePendingContact(PendingContactId p) throws DbException;

 	/**
 	 * Returns the contact with the given ID.
@@ -44,27 +151,37 @@ public interface ContactManager {
 	Contact getContact(ContactId c) throws DbException;

 	/**
-	 * Returns the contact with the given remoteAuthorId
-	 * that was added by the LocalAuthor with the given localAuthorId
+	 * Returns the contact with the given ID.
+	 */
+	Contact getContact(Transaction txn, ContactId c) throws DbException;
+
+	/**
+	 * Returns the contact with the given {@code remoteAuthorId}
+	 * that belongs to the local pseudonym with the given {@code localAuthorId}.
 	 *
-	 * @throws org.briarproject.bramble.api.db.NoSuchContactException
+	 * @throws NoSuchContactException If the contact is not in the database
 	 */
 	Contact getContact(AuthorId remoteAuthorId, AuthorId localAuthorId)
 			throws DbException;

 	/**
-	 * Returns the contact with the given remoteAuthorId
-	 * that was added by the LocalAuthor with the given localAuthorId
+	 * Returns the contact with the given {@code remoteAuthorId}
+	 * that belongs to the local pseudonym with the given {@code localAuthorId}.
 	 *
-	 * @throws org.briarproject.bramble.api.db.NoSuchContactException
+	 * @throws NoSuchContactException If the contact is not in the database
 	 */
 	Contact getContact(Transaction txn, AuthorId remoteAuthorId,
 			AuthorId localAuthorId) throws DbException;

 	/**
-	 * Returns all active contacts.
+	 * Returns all contacts.
 	 */
-	Collection<Contact> getActiveContacts() throws DbException;
+	Collection<Contact> getContacts() throws DbException;
+
+	/**
+	 * Returns all contacts.
+	 */
+	Collection<Contact> getContacts(Transaction txn) throws DbException;

 	/**
 	 * Removes a contact and all associated state.
@@ -77,28 +194,47 @@ public interface ContactManager {
 	void removeContact(Transaction txn, ContactId c) throws DbException;

 	/**
-	 * Marks a contact as active or inactive.
+	 * Sets an alias for the contact or unsets it if {@code alias} is null.
 	 */
-	void setContactActive(Transaction txn, ContactId c, boolean active)
+	void setContactAlias(Transaction txn, ContactId c, @Nullable String alias)
 			throws DbException;

 	/**
-	 * Return true if a contact with this name and public key already exists
+	 * Sets an alias for the contact or unsets it if {@code alias} is null.
+	 */
+	void setContactAlias(ContactId c, @Nullable String alias)
+			throws DbException;
+
+	/**
+	 * Returns true if a contact with this {@code remoteAuthorId} belongs to
+	 * the local pseudonym with this {@code localAuthorId}.
 	 */
 	boolean contactExists(Transaction txn, AuthorId remoteAuthorId,
 			AuthorId localAuthorId) throws DbException;

 	/**
-	 * Return true if a contact with this name and public key already exists
+	 * Returns true if a contact with this {@code remoteAuthorId} belongs to
+	 * the local pseudonym with this {@code localAuthorId}.
 	 */
 	boolean contactExists(AuthorId remoteAuthorId, AuthorId localAuthorId)
 			throws DbException;

-	interface AddContactHook {
-		void addingContact(Transaction txn, Contact c) throws DbException;
-	}
+	interface ContactHook {

-	interface RemoveContactHook {
+		/**
+		 * Called when a contact is being added.
+		 *
+		 * @param txn A read-write transaction
+		 * @param c The contact that is being added
+		 */
+		void addingContact(Transaction txn, Contact c) throws DbException;
+
+		/**
+		 * Called when a contact is being removed
+		 *
+		 * @param txn A read-write transaction
+		 * @param c The contact that is being removed
+		 */
 		void removingContact(Transaction txn, Contact c) throws DbException;
 	}
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/HandshakeLinkConstants.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/HandshakeLinkConstants.java
@@ -0,0 +1,34 @@
+package org.briarproject.bramble.api.contact;
+
+import java.util.regex.Pattern;
+
+public interface HandshakeLinkConstants {
+
+	/**
+	 * The current version of the handshake link format.
+	 */
+	int FORMAT_VERSION = 0;
+
+	/**
+	 * The length of a base32-encoded handshake link in bytes, excluding the
+	 * 'briar://' prefix.
+	 */
+	int BASE32_LINK_BYTES = 53;
+
+	/**
+	 * The length of a raw handshake link in bytes, before base32 encoding.
+	 */
+	int RAW_LINK_BYTES = 33;
+
+	/**
+	 * Regular expression for matching handshake links, including or excluding
+	 * the 'briar://' prefix.
+	 */
+	Pattern LINK_REGEX =
+			Pattern.compile("(briar://)?([a-z2-7]{" + BASE32_LINK_BYTES + "})");
+
+	/**
+	 * Label for hashing handshake public keys to calculate their identifiers.
+	 */
+	String ID_LABEL = "org.briarproject.bramble/HANDSHAKE_KEY_ID";
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/HandshakeManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/HandshakeManager.java
@@ -0,0 +1,45 @@
+package org.briarproject.bramble.api.contact;
+
+import org.briarproject.bramble.api.crypto.SecretKey;
+import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.transport.StreamWriter;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+@NotNullByDefault
+public interface HandshakeManager {
+
+	/**
+	 * Handshakes with the given pending contact. Returns an ephemeral master
+	 * key authenticated with both parties' handshake key pairs and a flag
+	 * indicating whether the local peer is Alice or Bob.
+	 *
+	 * @param in An incoming stream for the handshake, which must be secured in
+	 * handshake mode
+	 * @param out An outgoing stream for the handshake, which must be secured
+	 * in handshake mode
+	 */
+	HandshakeResult handshake(PendingContactId p, InputStream in,
+			StreamWriter out) throws DbException, IOException;
+
+	class HandshakeResult {
+
+		private final SecretKey masterKey;
+		private final boolean alice;
+
+		public HandshakeResult(SecretKey masterKey, boolean alice) {
+			this.masterKey = masterKey;
+			this.alice = alice;
+		}
+
+		public SecretKey getMasterKey() {
+			return masterKey;
+		}
+
+		public boolean isAlice() {
+			return alice;
+		}
+	}
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/PendingContact.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/PendingContact.java
@@ -0,0 +1,51 @@
+package org.briarproject.bramble.api.contact;
+
+import org.briarproject.bramble.api.crypto.PublicKey;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.concurrent.Immutable;
+
+@Immutable
+@NotNullByDefault
+public class PendingContact {
+
+	private final PendingContactId id;
+	private final PublicKey publicKey;
+	private final String alias;
+	private final long timestamp;
+
+	public PendingContact(PendingContactId id, PublicKey publicKey,
+			String alias, long timestamp) {
+		this.id = id;
+		this.publicKey = publicKey;
+		this.alias = alias;
+		this.timestamp = timestamp;
+	}
+
+	public PendingContactId getId() {
+		return id;
+	}
+
+	public PublicKey getPublicKey() {
+		return publicKey;
+	}
+
+	public String getAlias() {
+		return alias;
+	}
+
+	public long getTimestamp() {
+		return timestamp;
+	}
+
+	@Override
+	public int hashCode() {
+		return id.hashCode();
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		return o instanceof PendingContact &&
+				id.equals(((PendingContact) o).id);
+	}
+}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/PendingContactId.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/PendingContactId.java
@@ -0,0 +1,25 @@
+package org.briarproject.bramble.api.contact;
+
+import org.briarproject.bramble.api.UniqueId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.ThreadSafe;
+
+/**
+ * Type-safe wrapper for a byte array that uniquely identifies a
+ * {@link PendingContact}.
+ */
+@ThreadSafe
+@NotNullByDefault
+public class PendingContactId extends UniqueId {
+
+	public PendingContactId(byte[] id) {
+		super(id);
+	}
+
+	@Override
+	public boolean equals(@Nullable Object o) {
+		return o instanceof PendingContactId && super.equals(o);
+	}
+}
--- a/Show More
+++ b/Show More