diff --git a/briar-android/src/main/java/org/briarproject/briar/android/test/TestDataActivity.java b/briar-android/src/main/java/org/briarproject/briar/android/test/TestDataActivity.java
index e6b36f405..cac5d015f 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/test/TestDataActivity.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/test/TestDataActivity.java
@@ -24,9 +24,10 @@ public class TestDataActivity extends BriarActivity {
 	@Inject
 	TestDataCreator testDataCreator;
 
-	private TextView contactsTextView, forumsTextView;
+	private TextView contactsTextView, forumsTextView, privateGroupsTextView;
 	private SeekBar contactsSeekBar, messagesSeekBar, avatarsSeekBar,
-			blogPostsSeekBar, forumsSeekBar, forumPostsSeekBar;
+			blogPostsSeekBar, forumsSeekBar, forumPostsSeekBar,
+			privateGroupsSeekBar, privateGroupPostsSeekBar;
 
 	@Override
 	public void onCreate(Bundle bundle) {
@@ -46,28 +47,26 @@ public class TestDataActivity extends BriarActivity {
 		forumsTextView = findViewById(R.id.TextViewForumsSb);
 		TextView forumPostsTextView =
 				findViewById(R.id.TextViewForumMessagesSb);
+		privateGroupsTextView = findViewById(R.id.TextViewPrivateGroupsSb);
+		TextView privateGroupPostsTextView =
+				findViewById(R.id.TextViewPrivateGroupMessagesSb);
 		contactsSeekBar = findViewById(R.id.seekBarContacts);
 		messagesSeekBar = findViewById(R.id.seekBarMessages);
 		avatarsSeekBar = findViewById(R.id.seekBarAvatars);
 		blogPostsSeekBar = findViewById(R.id.seekBarBlogPosts);
 		forumsSeekBar = findViewById(R.id.seekBarForums);
 		forumPostsSeekBar = findViewById(R.id.seekBarForumMessages);
+		privateGroupsSeekBar = findViewById(R.id.seekBarPrivateGroups);
+		privateGroupPostsSeekBar =
+				findViewById(R.id.seekBarPrivateGroupMessages);
 
-		contactsSeekBar
-				.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
+		contactsSeekBar.setOnSeekBarChangeListener(
+				new AbstractOnSeekBarChangeListener() {
 					@Override
-					public void onProgressChanged(SeekBar seekBar,
-							int progress, boolean fromUser) {
+					public void onProgressChanged(SeekBar seekBar, int progress,
+							boolean fromUser) {
 						contactsTextView.setText(String.valueOf(progress + 1));
 					}
-
-					@Override
-					public void onStartTrackingTouch(SeekBar seekBar) {
-					}
-
-					@Override
-					public void onStopTrackingTouch(SeekBar seekBar) {
-					}
 				});
 
 		messagesSeekBar.setOnSeekBarChangeListener(
@@ -76,35 +75,39 @@ public class TestDataActivity extends BriarActivity {
 				new OnSeekBarChangeUpdateProgress(avatarsTextView));
 		blogPostsSeekBar.setOnSeekBarChangeListener(
 				new OnSeekBarChangeUpdateProgress(blogPostsTextView));
-		forumsSeekBar
-				.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
+		forumsSeekBar.setOnSeekBarChangeListener(
+				new AbstractOnSeekBarChangeListener() {
 					@Override
-					public void onProgressChanged(SeekBar seekBar,
-							int progress, boolean fromUser) {
+					public void onProgressChanged(SeekBar seekBar, int progress,
+							boolean fromUser) {
 						forumsTextView.setText(String.valueOf(progress));
 						forumPostsSeekBar.setEnabled(progress > 0);
 					}
-
-					@Override
-					public void onStartTrackingTouch(SeekBar seekBar) {
-					}
-
-					@Override
-					public void onStopTrackingTouch(SeekBar seekBar) {
-					}
 				});
 		forumPostsSeekBar.setOnSeekBarChangeListener(
 				new OnSeekBarChangeUpdateProgress(forumPostsTextView));
-
-		findViewById(R.id.buttonZeroValues).setOnClickListener(
-				v -> {
-					contactsSeekBar.setProgress(0);
-					messagesSeekBar.setProgress(0);
-					avatarsSeekBar.setProgress(0);
-					blogPostsSeekBar.setProgress(0);
-					forumsSeekBar.setProgress(0);
-					forumPostsSeekBar.setProgress(0);
+		privateGroupsSeekBar.setOnSeekBarChangeListener(
+				new AbstractOnSeekBarChangeListener() {
+					@Override
+					public void onProgressChanged(SeekBar seekBar, int progress,
+							boolean fromUser) {
+						privateGroupsTextView.setText(String.valueOf(progress));
+						privateGroupPostsSeekBar.setEnabled(progress > 0);
+					}
 				});
+		privateGroupPostsSeekBar.setOnSeekBarChangeListener(
+				new OnSeekBarChangeUpdateProgress(privateGroupPostsTextView));
+
+		findViewById(R.id.buttonZeroValues).setOnClickListener(v -> {
+			contactsSeekBar.setProgress(0);
+			messagesSeekBar.setProgress(0);
+			avatarsSeekBar.setProgress(0);
+			blogPostsSeekBar.setProgress(0);
+			forumsSeekBar.setProgress(0);
+			forumPostsSeekBar.setProgress(0);
+			privateGroupsSeekBar.setProgress(0);
+			privateGroupPostsSeekBar.setProgress(0);
+		});
 
 		findViewById(R.id.buttonCreateTestData).setOnClickListener(
 				v -> createTestData());
@@ -114,7 +117,9 @@ public class TestDataActivity extends BriarActivity {
 		testDataCreator.createTestData(contactsSeekBar.getProgress() + 1,
 				messagesSeekBar.getProgress(), avatarsSeekBar.getProgress(),
 				blogPostsSeekBar.getProgress(), forumsSeekBar.getProgress(),
-				forumPostsSeekBar.getProgress());
+				forumPostsSeekBar.getProgress(),
+				privateGroupsSeekBar.getProgress(),
+				privateGroupPostsSeekBar.getProgress());
 		Intent intent = new Intent(this, ENTRY_ACTIVITY);
 		intent.addFlags(FLAG_ACTIVITY_CLEAR_TOP);
 		startActivity(intent);
@@ -136,7 +141,7 @@ public class TestDataActivity extends BriarActivity {
 	}
 
 	private static class OnSeekBarChangeUpdateProgress
-			implements OnSeekBarChangeListener {
+			extends AbstractOnSeekBarChangeListener {
 		private final TextView textView;
 
 		private OnSeekBarChangeUpdateProgress(TextView textView) {
@@ -148,7 +153,10 @@ public class TestDataActivity extends BriarActivity {
 				boolean fromUser) {
 			textView.setText(String.valueOf(progress));
 		}
+	}
 
+	private abstract static class AbstractOnSeekBarChangeListener
+			implements OnSeekBarChangeListener {
 		@Override
 		public void onStartTrackingTouch(SeekBar seekBar) {
 		}
@@ -157,5 +165,4 @@ public class TestDataActivity extends BriarActivity {
 		public void onStopTrackingTouch(SeekBar seekBar) {
 		}
 	}
-
 }
diff --git a/briar-android/src/main/res/layout/activity_test_data.xml b/briar-android/src/main/res/layout/activity_test_data.xml
index 25ff0db87..0cb9613ac 100644
--- a/briar-android/src/main/res/layout/activity_test_data.xml
+++ b/briar-android/src/main/res/layout/activity_test_data.xml
@@ -191,6 +191,66 @@
 			app:layout_constraintEnd_toEndOf="parent"
 			app:layout_constraintTop_toBottomOf="@+id/textViewForumMessages" />
 
+		<TextView
+			android:id="@+id/textViewPrivateGroups"
+			android:layout_width="match_parent"
+			android:layout_height="wrap_content"
+			android:layout_margin="@dimen/margin_medium"
+			android:text="Number of private groups"
+			app:layout_constraintStart_toStartOf="parent"
+			app:layout_constraintTop_toBottomOf="@+id/seekBarForumMessages" />
+
+		<SeekBar
+			android:id="@+id/seekBarPrivateGroups"
+			android:layout_width="0dp"
+			android:layout_height="wrap_content"
+			android:max="50"
+			android:paddingTop="5dp"
+			android:progress="5"
+			app:layout_constraintEnd_toStartOf="@+id/TextViewPrivateGroupsSb"
+			app:layout_constraintStart_toStartOf="parent"
+			app:layout_constraintTop_toBottomOf="@+id/textViewPrivateGroups" />
+
+		<TextView
+			android:id="@+id/TextViewPrivateGroupsSb"
+			android:layout_width="wrap_content"
+			android:layout_height="wrap_content"
+			android:ems="2"
+			android:text="5"
+			app:layout_constraintBottom_toBottomOf="@+id/seekBarPrivateGroups"
+			app:layout_constraintEnd_toEndOf="parent"
+			app:layout_constraintTop_toBottomOf="@+id/textViewPrivateGroups" />
+
+		<TextView
+			android:id="@+id/textViewPrivateGroupMessages"
+			android:layout_width="match_parent"
+			android:layout_height="wrap_content"
+			android:layout_margin="@dimen/margin_medium"
+			android:text="Number of private group messages"
+			app:layout_constraintStart_toStartOf="parent"
+			app:layout_constraintTop_toBottomOf="@+id/seekBarPrivateGroups" />
+
+		<SeekBar
+			android:id="@+id/seekBarPrivateGroupMessages"
+			android:layout_width="0dp"
+			android:layout_height="wrap_content"
+			android:max="50"
+			android:paddingTop="5dp"
+			android:progress="20"
+			app:layout_constraintEnd_toStartOf="@+id/TextViewPrivateGroupMessagesSb"
+			app:layout_constraintStart_toStartOf="parent"
+			app:layout_constraintTop_toBottomOf="@+id/textViewPrivateGroupMessages" />
+
+		<TextView
+			android:id="@+id/TextViewPrivateGroupMessagesSb"
+			android:layout_width="wrap_content"
+			android:layout_height="wrap_content"
+			android:ems="2"
+			android:text="20"
+			app:layout_constraintBottom_toBottomOf="@+id/seekBarPrivateGroupMessages"
+			app:layout_constraintEnd_toEndOf="parent"
+			app:layout_constraintTop_toBottomOf="@+id/textViewPrivateGroupMessages" />
+
 		<Button
 			android:id="@+id/buttonZeroValues"
 			style="@style/BriarButton"
@@ -201,7 +261,7 @@
 			android:text="Zero values"
 			app:layout_constraintEnd_toEndOf="parent"
 			app:layout_constraintStart_toStartOf="parent"
-			app:layout_constraintTop_toBottomOf="@+id/seekBarForumMessages"
+			app:layout_constraintTop_toBottomOf="@+id/seekBarPrivateGroupMessages"
 			app:layout_constraintVertical_bias="1.0" />
 
 		<Button
diff --git a/briar-api/src/main/java/org/briarproject/briar/api/test/TestDataCreator.java b/briar-api/src/main/java/org/briarproject/briar/api/test/TestDataCreator.java
index b40fd67d3..01c301f02 100644
--- a/briar-api/src/main/java/org/briarproject/briar/api/test/TestDataCreator.java
+++ b/briar-api/src/main/java/org/briarproject/briar/api/test/TestDataCreator.java
@@ -19,9 +19,12 @@ public interface TestDataCreator {
 	 * @param numBlogPosts Number of blog posts to create.
 	 * @param numForums Number of forums to create.
 	 * @param numForumPosts Number of forum posts to create per forum.
+	 * @param numPrivateGroups Number of private groups to create.
+	 * @param numPrivateGroupMessages Number of messages to create per private group.
 	 */
 	void createTestData(int numContacts, int numPrivateMsgs, int avatarPercent,
-			int numBlogPosts, int numForums, int numForumPosts);
+			int numBlogPosts, int numForums, int numForumPosts,
+			int numPrivateGroups, int numPrivateGroupMessages);
 
 	@IoExecutor
 	Contact addContact(String name, boolean alias, boolean avatar)
diff --git a/briar-core/src/main/java/org/briarproject/briar/test/TestDataCreatorImpl.java b/briar-core/src/main/java/org/briarproject/briar/test/TestDataCreatorImpl.java
index 5ff3640d7..9b8a0afdc 100644
--- a/briar-core/src/main/java/org/briarproject/briar/test/TestDataCreatorImpl.java
+++ b/briar-core/src/main/java/org/briarproject/briar/test/TestDataCreatorImpl.java
@@ -6,6 +6,7 @@ import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
+import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
@@ -38,6 +39,12 @@ import org.briarproject.briar.api.forum.ForumPost;
 import org.briarproject.briar.api.messaging.MessagingManager;
 import org.briarproject.briar.api.messaging.PrivateMessage;
 import org.briarproject.briar.api.messaging.PrivateMessageFactory;
+import org.briarproject.briar.api.privategroup.GroupMessage;
+import org.briarproject.briar.api.privategroup.GroupMessageFactory;
+import org.briarproject.briar.api.privategroup.PrivateGroup;
+import org.briarproject.briar.api.privategroup.PrivateGroupFactory;
+import org.briarproject.briar.api.privategroup.PrivateGroupManager;
+import org.briarproject.briar.api.privategroup.invitation.GroupInvitationFactory;
 import org.briarproject.briar.api.test.TestAvatarCreator;
 import org.briarproject.briar.api.test.TestDataCreator;
 import org.briarproject.nullsafety.NotNullByDefault;
@@ -89,6 +96,10 @@ public class TestDataCreatorImpl implements TestDataCreator {
 	private final MessagingManager messagingManager;
 	private final BlogManager blogManager;
 	private final ForumManager forumManager;
+	private final PrivateGroupManager privateGroupManager;
+	private final PrivateGroupFactory privateGroupFactory;
+	private final GroupMessageFactory groupMessageFactory;
+	private final GroupInvitationFactory groupInvitationFactory;
 	private final TestAvatarCreator testAvatarCreator;
 	private final AvatarMessageEncoder avatarMessageEncoder;
 
@@ -111,6 +122,10 @@ public class TestDataCreatorImpl implements TestDataCreator {
 			TransportPropertyManager transportPropertyManager,
 			MessagingManager messagingManager, BlogManager blogManager,
 			ForumManager forumManager,
+			PrivateGroupManager privateGroupManager,
+			PrivateGroupFactory privateGroupFactory,
+			GroupMessageFactory groupMessageFactory,
+			GroupInvitationFactory groupInvitationFactory,
 			TestAvatarCreator testAvatarCreator,
 			AvatarMessageEncoder avatarMessageEncoder,
 			FeatureFlags featureFlags,
@@ -128,6 +143,10 @@ public class TestDataCreatorImpl implements TestDataCreator {
 		this.messagingManager = messagingManager;
 		this.blogManager = blogManager;
 		this.forumManager = forumManager;
+		this.privateGroupManager = privateGroupManager;
+		this.privateGroupFactory = privateGroupFactory;
+		this.groupMessageFactory = groupMessageFactory;
+		this.groupInvitationFactory = groupInvitationFactory;
 		this.testAvatarCreator = testAvatarCreator;
 		this.avatarMessageEncoder = avatarMessageEncoder;
 		this.featureFlags = featureFlags;
@@ -137,14 +156,16 @@ public class TestDataCreatorImpl implements TestDataCreator {
 	@Override
 	public void createTestData(int numContacts, int numPrivateMsgs,
 			int avatarPercent, int numBlogPosts, int numForums,
-			int numForumPosts) {
+			int numForumPosts, int numPrivateGroups,
+			int numPrivateGroupMessages) {
 		if (numContacts == 0) throw new IllegalArgumentException();
 		if (avatarPercent < 0 || avatarPercent > 100)
 			throw new IllegalArgumentException();
 		ioExecutor.execute(() -> {
 			try {
 				createTestDataOnIoExecutor(numContacts, numPrivateMsgs,
-						avatarPercent, numBlogPosts, numForums, numForumPosts);
+						avatarPercent, numBlogPosts, numForums, numForumPosts,
+						numPrivateGroups, numPrivateGroupMessages);
 			} catch (DbException e) {
 				logException(LOG, WARNING, e);
 			}
@@ -154,7 +175,8 @@ public class TestDataCreatorImpl implements TestDataCreator {
 	@IoExecutor
 	private void createTestDataOnIoExecutor(int numContacts, int numPrivateMsgs,
 			int avatarPercent, int numBlogPosts, int numForums,
-			int numForumPosts) throws DbException {
+			int numForumPosts, int numPrivateGroups,
+			int numPrivateGroupMessages) throws DbException {
 		List<Contact> contacts = createContacts(numContacts, avatarPercent);
 		createPrivateMessages(contacts, numPrivateMsgs);
 		createBlogPosts(contacts, numBlogPosts);
@@ -162,6 +184,12 @@ public class TestDataCreatorImpl implements TestDataCreator {
 		for (Forum forum : forums) {
 			createRandomForumPosts(forum, contacts, numForumPosts);
 		}
+		List<PrivateGroup> groups =
+				createPrivateGroups(contacts, numPrivateGroups);
+		for (PrivateGroup group : groups) {
+			createRandomPrivateGroupMessages(group, contacts,
+					numPrivateGroupMessages);
+		}
 	}
 
 	private List<Contact> createContacts(int numContacts, int avatarPercent)
@@ -464,6 +492,86 @@ public class TestDataCreatorImpl implements TestDataCreator {
 		}
 	}
 
+	private List<PrivateGroup> createPrivateGroups(List<Contact> contacts,
+			int numPrivateGroups) throws DbException {
+		if (!featureFlags.shouldEnablePrivateGroupsInCore()) return emptyList();
+		List<PrivateGroup> groups = new ArrayList<>(numPrivateGroups);
+		for (int i = 0; i < numPrivateGroups; i++) {
+			// create private group
+			String name = GROUP_NAMES[random.nextInt(GROUP_NAMES.length)];
+			LocalAuthor creator = identityManager.getLocalAuthor();
+			PrivateGroup group =
+					privateGroupFactory.createPrivateGroup(name, creator);
+			GroupMessage joinMsg = groupMessageFactory.createJoinMessage(
+					group.getId(),
+					clock.currentTimeMillis() - (long) (100 - i) * 60 * 1000,
+					creator
+			);
+			privateGroupManager.addPrivateGroup(group, joinMsg, true);
+			groups.add(group);
+		}
+		if (LOG.isLoggable(INFO)) {
+			LOG.info("Created " + numPrivateGroups + " private groups.");
+		}
+		return groups;
+	}
+
+	private void createRandomPrivateGroupMessages(PrivateGroup group,
+			List<Contact> contacts, int amount) throws DbException {
+		List<GroupMessage> messages = new ArrayList<>();
+		PrivateKey creatorPrivateKey =
+				identityManager.getLocalAuthor().getPrivateKey();
+		int numMembers = random.nextInt(contacts.size());
+		if (numMembers == 0) numMembers++;
+		Map<Contact, MessageId> membersLastMessage = new HashMap<>();
+		List<Contact> members = new ArrayList<>(numMembers);
+		for (int i = 0; i < numMembers; i++) {
+			Contact contact = contacts.get(i);
+			members.add(contact);
+		}
+		for (int i = 0; i < amount; i++) {
+			Contact contact = members.get(random.nextInt(numMembers));
+			LocalAuthor author = localAuthors.get(contact);
+			long timestamp =
+					clock.currentTimeMillis() -
+							(long) (amount - i) * 60 * 1000;
+
+			GroupMessage msg;
+			if (!membersLastMessage.containsKey(contact)) {
+				// join message as first message of member
+				shareGroup(contact.getId(), group.getId());
+				long inviteTimestamp = timestamp - 1;
+				byte[] creatorSignature =
+						groupInvitationFactory.signInvitation(contact,
+								group.getId(), inviteTimestamp,
+								creatorPrivateKey);
+				msg = groupMessageFactory.createJoinMessage(group.getId(),
+								timestamp, author, inviteTimestamp,
+								creatorSignature);
+			} else {
+				// random text after first message
+				String text = getRandomText();
+				MessageId parent = null;
+				if (random.nextBoolean() && messages.size() > 0) {
+					GroupMessage parentMessage =
+							messages.get(random.nextInt(messages.size()));
+					parent = parentMessage.getMessage().getId();
+				}
+				MessageId lastMsg = membersLastMessage.get(contact);
+				msg = groupMessageFactory.createGroupMessage(
+						group.getId(), timestamp, parent, author, text,
+						lastMsg);
+				messages.add(msg);
+			}
+			membersLastMessage.put(contact, msg.getMessage().getId());
+			db.transaction(false, txn ->
+					db.receiveMessage(txn, contact.getId(), msg.getMessage()));
+		}
+		if (LOG.isLoggable(INFO)) {
+			LOG.info("Created " + amount + " private group messages.");
+		}
+	}
+
 	private String getRandomText() {
 		int minLength = 3 + random.nextInt(500);
 		int maxWordLength = 15;