Group Android notifications by space and clear them on read.

Use stable per-room notification IDs with Directs/Spaces/Home channels and space group summaries so the shade nests deeper than a flat Messages list, and dismiss those tray entries when a room is marked read.

android/app/src/main/java/com/paarrot/app/MatrixSyncService.kt

@@ -172,7 +172,7 @@ class MatrixSyncService : Service() {
         val token = prefs.getString(EXTRA_TOKEN, null) ?: return
         val joinedRooms = sync.optJSONObject("rooms")?.optJSONObject("join") ?: return
         val nm = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
-        ensureMessageChannel(nm)
+        ensureMessageChannels(nm)
 
         val notifyCtx = loadNotifyContext(homeserver, token, myUserId)
 
@@ -225,7 +225,15 @@ class MatrixSyncService : Service() {
                         ?.let { downloadBitmap(it, token) }
                 } else null
 
-                showMessageNotification(nm, profile.displayName, body, profile.avatar, inlineImage)
+                showMessageNotification(
+                    nm,
+                    roomId,
+                    profile.displayName,
+                    body,
+                    profile.avatar,
+                    inlineImage,
+                    resolveGroupInfo(roomId, notifyCtx),
+                )
             }
         }
     }
@@ -445,27 +453,100 @@ class MatrixSyncService : Service() {
         }
     }
 
+    private data class NotificationGroupInfo(
+        val groupId: String,
+        val groupName: String,
+        val roomName: String,
+        val kind: String,
+    )
+
+    private fun resolveGroupInfo(roomId: String, ctx: NotifyContext): NotificationGroupInfo {
+        val mapped = loadNotificationGroupMap()[roomId]
+        if (mapped != null) return mapped
+
+        return if (ctx.directRoomIds.contains(roomId)) {
+            NotificationGroupInfo(
+                groupId = GROUP_DIRECTS,
+                groupName = "Direct messages",
+                roomName = roomId,
+                kind = "direct",
+            )
+        } else {
+            NotificationGroupInfo(
+                groupId = GROUP_HOME,
+                groupName = "Home",
+                roomName = roomId,
+                kind = "home",
+            )
+        }
+    }
+
+    private fun loadNotificationGroupMap(): Map<String, NotificationGroupInfo> {
+        val prefs = applicationContext.getSharedPreferences(SyncServicePlugin.PREFS, Context.MODE_PRIVATE)
+        val raw = prefs.getString(KEY_NOTIFICATION_GROUPS, null) ?: return emptyMap()
+        return try {
+            val root = JSONObject(raw)
+            val out = mutableMapOf<String, NotificationGroupInfo>()
+            val keys = root.keys()
+            while (keys.hasNext()) {
+                val roomId = keys.next()
+                val obj = root.optJSONObject(roomId) ?: continue
+                out[roomId] = NotificationGroupInfo(
+                    groupId = obj.optString("groupId").ifBlank { GROUP_HOME },
+                    groupName = obj.optString("groupName").ifBlank { "Home" },
+                    roomName = obj.optString("roomName").ifBlank { roomId },
+                    kind = obj.optString("kind").ifBlank { "home" },
+                )
+            }
+            out
+        } catch (e: Exception) {
+            Log.w(TAG, "Failed to parse notification group map: ${e.message}")
+            emptyMap()
+        }
+    }
+
+    private fun channelIdForKind(kind: String): String = when (kind) {
+        "direct" -> CHANNEL_DIRECTS
+        "space" -> CHANNEL_SPACES
+        else -> CHANNEL_HOME
+    }
+
     private fun showMessageNotification(
         nm: NotificationManager,
+        roomId: String,
         sender: String,
         body: String,
         largeIcon: Bitmap? = null,
         inlineImage: Bitmap? = null,
+        groupInfo: NotificationGroupInfo,
     ) {
         val launchIntent = packageManager.getLaunchIntentForPackage(packageName)
             ?: Intent(this, MainActivity::class.java)
+        val roomNotifId = notificationIdForRoom(roomId)
         val pi = PendingIntent.getActivity(
-            this, 0, launchIntent,
+            this, roomNotifId, launchIntent,
             PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE,
         )
 
-        val builder = NotificationCompat.Builder(this, CHANNEL_MESSAGES)
+        val isDm = groupInfo.kind == "direct"
+        val title = if (isDm) sender else groupInfo.roomName.ifBlank { sender }
+        val text = if (isDm) body else "$sender: $body"
+        val channelId = channelIdForKind(groupInfo.kind)
+
+        val builder = NotificationCompat.Builder(this, channelId)
             .setSmallIcon(R.drawable.ic_stat_paarrot)
-            .setContentTitle(sender)
-            .setContentText(body)
+            .setContentTitle(title)
+            .setContentText(text)
             .setAutoCancel(true)
             .setContentIntent(pi)
             .setPriority(NotificationCompat.PRIORITY_HIGH)
+            .setCategory(NotificationCompat.CATEGORY_MESSAGE)
+            .setGroup(groupInfo.groupId)
+            .setOnlyAlertOnce(true)
+            .setSubText(groupInfo.groupName)
+
+        builder.extras.putString(EXTRA_ROOM_ID, roomId)
+        builder.extras.putString(EXTRA_GROUP_ID, groupInfo.groupId)
 
         if (largeIcon != null) builder.setLargeIcon(largeIcon)
 
@@ -475,9 +556,36 @@ class MatrixSyncService : Service() {
                     .bigPicture(inlineImage)
                     .bigLargeIcon(null as Bitmap?)
             )
+        } else {
+            builder.setStyle(
+                NotificationCompat.BigTextStyle()
+                    .bigText(text)
+                    .setSummaryText(groupInfo.groupName)
+            )
         }
 
-        nm.notify(System.currentTimeMillis().toInt(), builder.build())
+        // Stable per-room id replaces the previous tray entry instead of stacking.
+        nm.notify(roomNotifId, builder.build())
+
+        // Nest under Direct messages / Space name / Home in the notification shade.
+        val summaryId = notificationIdForGroupSummary(groupInfo.groupId)
+        val summary = NotificationCompat.Builder(this, channelId)
+            .setSmallIcon(R.drawable.ic_stat_paarrot)
+            .setContentTitle(groupInfo.groupName)
+            .setContentText("New messages")
+            .setAutoCancel(true)
+            .setContentIntent(pi)
+            .setPriority(NotificationCompat.PRIORITY_HIGH)
+            .setCategory(NotificationCompat.CATEGORY_MESSAGE)
+            .setGroup(groupInfo.groupId)
+            .setGroupSummary(true)
+            .setStyle(
+                NotificationCompat.InboxStyle()
+                    .setBigContentTitle(groupInfo.groupName)
+                    .setSummaryText(groupInfo.groupName)
+            )
+        summary.extras.putString(EXTRA_GROUP_ID, groupInfo.groupId)
+        nm.notify(summaryId, summary.build())
     }
 
     private fun buildStatusNotification(): Notification {
@@ -511,21 +619,26 @@ class MatrixSyncService : Service() {
         }
     }
 
-    private fun ensureMessageChannel(nm: NotificationManager) {
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
-            val soundUri = Uri.parse("android.resource://$packageName/${R.raw.paarrot_notification}")
-            val channel = NotificationChannel(
-                CHANNEL_MESSAGES, "Messages",
-                NotificationManager.IMPORTANCE_HIGH,
-            ).apply {
-                description = "Matrix message notifications"
-                setSound(
-                    soundUri,
-                    AudioAttributes.Builder()
-                        .setUsage(AudioAttributes.USAGE_NOTIFICATION)
-                        .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
-                        .build(),
-                )
+    private fun ensureMessageChannels(nm: NotificationManager) {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) return
+
+        val soundUri = Uri.parse("android.resource://$packageName/${R.raw.paarrot_notification}")
+        val soundAttrs = AudioAttributes.Builder()
+            .setUsage(AudioAttributes.USAGE_NOTIFICATION)
+            .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
+            .build()
+
+        val channels = listOf(
+            Triple(CHANNEL_DIRECTS, "Direct messages", "One-to-one Matrix conversations"),
+            Triple(CHANNEL_SPACES, "Spaces", "Messages from rooms inside Spaces"),
+            Triple(CHANNEL_HOME, "Other rooms", "Rooms that are not in a Space"),
+            Triple(CHANNEL_MESSAGES, "Messages", "Legacy message channel"),
+        )
+
+        for ((id, name, description) in channels) {
+            val channel = NotificationChannel(id, name, NotificationManager.IMPORTANCE_HIGH).apply {
+                this.description = description
+                setSound(soundUri, soundAttrs)
             }
             nm.createNotificationChannel(channel)
         }
@@ -537,16 +650,79 @@ class MatrixSyncService : Service() {
         const val EXTRA_TOKEN = "access_token"
         const val EXTRA_USER_ID = "user_id"
         const val EXTRA_DEVICE_ID = "device_id"
+        const val EXTRA_ROOM_ID = "room_id"
+        const val EXTRA_GROUP_ID = "group_id"
         const val EXTRA_TRIGGER_REASON = "trigger_reason"
+        const val KEY_NOTIFICATION_GROUPS = "notification_groups"
         const val PREFS = "matrix_sync_prefs"
         const val KEY_SINCE = "since_token"
         private const val KEY_LAST_WAKE_MS = "last_wake_ms"
         private const val NOTIF_ID_STATUS = 1001
         private const val CHANNEL_STATUS = "sync_status"
         private const val CHANNEL_MESSAGES = "messages_paarrot"
+        private const val CHANNEL_DIRECTS = "messages_directs"
+        private const val CHANNEL_SPACES = "messages_spaces"
+        private const val CHANNEL_HOME = "messages_home"
+        private const val GROUP_DIRECTS = "paarrot_directs"
+        private const val GROUP_HOME = "paarrot_home"
         private const val MIN_WAKE_INTERVAL_MS = 7_500L
         const val MODE_ONE_SHOT = "one_shot"
 
+        /** Same hashing scheme as JS `notificationIdForRoom` so clear-on-read hits both paths. */
+        fun notificationIdForRoom(roomId: String): Int {
+            var hash = 0
+            for (ch in roomId) {
+                hash = (hash shl 5) - hash + ch.code
+            }
+            // Match JS Math.abs(...); avoid Int.MIN_VALUE abs edge case.
+            val positive = if (hash == Int.MIN_VALUE) 0 else kotlin.math.abs(hash)
+            var id = positive % 2147483647
+            if (id == 0 || id == NOTIF_ID_STATUS) {
+                id = NOTIF_ID_STATUS + 1
+            }
+            return id
+        }
+
+        fun notificationIdForGroupSummary(groupId: String): Int =
+            notificationIdForRoom("summary:$groupId")
+
+        /** Cancel the tray notification posted for [roomId], if any. */
+        fun clearRoomNotifications(context: Context, roomId: String) {
+            if (roomId.isBlank()) return
+            val nm = context.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
+            val roomNotifId = notificationIdForRoom(roomId)
+
+            var groupId: String? = null
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+                groupId = nm.activeNotifications
+                    .firstOrNull { it.id == roomNotifId }
+                    ?.notification?.extras?.getString(EXTRA_GROUP_ID)
+            }
+
+            nm.cancel(roomNotifId)
+
+            // Also drop any legacy stacked notifications that still carry this room id.
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+                for (active in nm.activeNotifications) {
+                    val tagged = active.notification.extras.getString(EXTRA_ROOM_ID)
+                    if (tagged == roomId && active.id != roomNotifId) {
+                        nm.cancel(active.id)
+                    }
+                }
+
+                if (!groupId.isNullOrBlank()) {
+                    val summaryId = notificationIdForGroupSummary(groupId)
+                    val siblingsRemain = nm.activeNotifications.any { active ->
+                        active.id != summaryId &&
+                            active.notification.extras.getString(EXTRA_GROUP_ID) == groupId
+                    }
+                    if (!siblingsRemain) {
+                        nm.cancel(summaryId)
+                    }
+                }
+            }
+        }
+
         /** Set by [SyncServicePlugin] — true when the Capacitor WebView UI is visible. */
         @Volatile
         var appInForeground = false

android/app/src/main/java/com/paarrot/app/SyncServicePlugin.kt

@@ -17,6 +17,8 @@ import com.getcapacitor.annotation.CapacitorPlugin
  * - `stop()` — clear persisted credentials and unregister UnifiedPush
  * - `setAppForeground({ foreground })` — tell the service whether the app UI is visible
  * - `getStatus()` — returns current fetch and UnifiedPush state
+ * - `clearRoomNotifications({ roomId })` — dismiss native tray notifs for a room
+ * - `setNotificationGroups({ rooms })` — persist space/DM grouping for tray nesting
  */
 @CapacitorPlugin(name = "MatrixBackgroundSync")
 class SyncServicePlugin : Plugin() {
@@ -97,6 +99,31 @@ class SyncServicePlugin : Plugin() {
         call.resolve(result)
     }
 
+    /**
+     * Cancels native tray notifications for a Matrix room after it has been marked as read.
+     */
+    @PluginMethod
+    fun clearRoomNotifications(call: PluginCall) {
+        val roomId = call.getString("roomId")
+            ?: return call.reject("roomId required")
+        MatrixSyncService.clearRoomNotifications(context, roomId)
+        call.resolve(JSObject().put("cleared", true))
+    }
+
+    /**
+     * Persists room → space/group metadata from the JS layer so background
+     * notifications can nest under Direct messages / Space name / Home.
+     */
+    @PluginMethod
+    fun setNotificationGroups(call: PluginCall) {
+        val rooms = call.getObject("rooms")
+            ?: return call.reject("rooms required")
+        context.getSharedPreferences(PREFS, Context.MODE_PRIVATE).edit()
+            .putString(MatrixSyncService.KEY_NOTIFICATION_GROUPS, rooms.toString())
+            .apply()
+        call.resolve(JSObject().put("success", true))
+    }
+
     companion object {
         const val PREFS = "sync_service_prefs"
     }

overlay/src/app/pages/client/ClientNonUIFeatures.tsx

@@ -35,12 +35,17 @@ import {
   isCapacitorNative,
   sendNotification,
   setupNotificationTapListener,
+  clearNotificationsForRoom,
+  NOTIF_GROUP_DIRECTS,
+  NOTIF_GROUP_HOME,
+  type NotificationGroupInfo,
 } from '../../utils/tauri';
 import { setPaarrotNavigate, initPaarrotAPI } from '../../paarrot-api';
 import {
   startBackgroundSync,
   stopBackgroundSync,
   setAppForegroundState,
+  syncNotificationGroupMap,
 } from '../../utils/backgroundSync';
 import {
   TUploadItem,
@@ -226,6 +231,20 @@ function MessageNotifications() {
     });
   }, [navigate]);
 
+  const roomToUnread = useAtomValue(roomToUnreadAtom);
+  const previousUnreadRoomsRef = useRef<Set<string>>(new Set());
+
+  // Dismiss OS notifications when a room's unread is cleared (local read or receipt).
+  useEffect(() => {
+    const currentRooms = new Set(roomToUnread.keys());
+    for (const roomId of previousUnreadRoomsRef.current) {
+      if (!currentRooms.has(roomId)) {
+        void clearNotificationsForRoom(roomId);
+      }
+    }
+    previousUnreadRoomsRef.current = currentRooms;
+  }, [roomToUnread]);
+
   const notify = useCallback(
     ({
       roomName,
@@ -244,8 +263,42 @@ function MessageNotifications() {
       eventId: string;
       isDm: boolean;
     }) => {
-      const notificationTitle = username;
-      const notificationBody = messageBody || 'New message';
+      let group: NotificationGroupInfo;
+      if (isDm) {
+        group = {
+          groupId: NOTIF_GROUP_DIRECTS,
+          groupName: 'Direct messages',
+          kind: 'direct',
+          roomName,
+        };
+      } else {
+        const orphanParents = getOrphanParents(roomToParents, roomId);
+        if (orphanParents.length > 0 && mx) {
+          const parentSpace = guessPerfectParent(mx, roomId, orphanParents) ?? orphanParents[0];
+          const spaceRoom = mx.getRoom(parentSpace);
+          group = {
+            groupId: parentSpace,
+            groupName: spaceRoom?.name || 'Space',
+            kind: 'space',
+            roomName,
+          };
+        } else {
+          group = {
+            groupId: NOTIF_GROUP_HOME,
+            groupName: 'Home',
+            kind: 'home',
+            roomName,
+          };
+        }
+      }
+
+      // DMs: sender as title. Rooms: room name as title, sender in body.
+      const notificationTitle = isDm ? username : roomName || username;
+      const notificationBody = isDm
+        ? messageBody || 'New message'
+        : messageBody
+          ? `${username}: ${messageBody}`
+          : `${username} sent a message`;
 
       /** Replicates TitleBar click navigation logic */
       const navigateToRoom = () => {
@@ -291,6 +344,8 @@ function MessageNotifications() {
           title: notificationTitle,
           body: notificationBody,
           path: roomPath,
+          roomId,
+          group,
           onClick: () => {
             if (!window.closed) navigate(roomPath);
           },
@@ -449,6 +504,9 @@ function MessageNotifications() {
  */
 function BackgroundSyncSetup() {
   const mx = useMatrixClient();
+  const mDirects = useAtomValue(mDirectAtom);
+  const roomToParents = useAtomValue(roomToParentsAtom);
+
   // Try to make a simple fetch to verify component is rendering
   try {
     fetch('/_matrix/client/v3/sync', { method: 'HEAD' }).catch(() => {});
@@ -468,6 +526,49 @@ function BackgroundSyncSetup() {
     };
   }, [mx]);
 
+  // Keep native background notifier informed of space → room grouping.
+  useEffect(() => {
+    const rooms: Record<
+      string,
+      { groupId: string; groupName: string; roomName: string; kind: 'direct' | 'space' | 'home' }
+    > = {};
+
+    for (const room of mx.getRooms()) {
+      if (room.isSpaceRoom()) continue;
+      const roomId = room.roomId;
+      const roomName = room.name || roomId;
+      if (mDirects.has(roomId)) {
+        rooms[roomId] = {
+          groupId: NOTIF_GROUP_DIRECTS,
+          groupName: 'Direct messages',
+          roomName,
+          kind: 'direct',
+        };
+        continue;
+      }
+      const orphanParents = getOrphanParents(roomToParents, roomId);
+      if (orphanParents.length > 0) {
+        const parentSpace = guessPerfectParent(mx, roomId, orphanParents) ?? orphanParents[0];
+        const spaceRoom = mx.getRoom(parentSpace);
+        rooms[roomId] = {
+          groupId: parentSpace,
+          groupName: spaceRoom?.name || 'Space',
+          roomName,
+          kind: 'space',
+        };
+      } else {
+        rooms[roomId] = {
+          groupId: NOTIF_GROUP_HOME,
+          groupName: 'Home',
+          roomName,
+          kind: 'home',
+        };
+      }
+    }
+
+    void syncNotificationGroupMap(rooms);
+  }, [mx, mDirects, roomToParents]);
+
   return null;
 }
 

overlay/src/app/utils/backgroundSync.ts

@@ -10,6 +10,10 @@ type UnifiedPushStatus = {
   distributors: string[] | string;
 };
 
+type ClearRoomNotificationsResult = {
+  cleared: boolean;
+};
+
 type UnifiedPushEndpointEvent = {
   endpoint: string;
   previousEndpoint: string;
@@ -48,6 +52,18 @@ interface MatrixBackgroundSyncPlugin {
   setAppForeground(options: { foreground: boolean }): Promise<void>;
   /** Returns fetch state and current UnifiedPush registration details. */
   getStatus(): Promise<UnifiedPushStatus>;
+  /** Cancel native tray notifications posted for a Matrix room. */
+  clearRoomNotifications(options: { roomId: string }): Promise<ClearRoomNotificationsResult>;
+  /**
+   * Persist room → space/group metadata so background notifications can nest
+   * under Direct messages / Space name / Home.
+   */
+  setNotificationGroups(options: {
+    rooms: Record<
+      string,
+      { groupId: string; groupName: string; roomName: string; kind: string }
+    >;
+  }): Promise<{ success: boolean }>;
   addListener(
     eventName: 'unifiedPushNewEndpoint',
     listenerFunc: (event: UnifiedPushEndpointEvent) => void
@@ -516,3 +532,35 @@ export const getBackgroundSyncStatus = async (): Promise<UnifiedPushStatus | und
     return undefined;
   }
 };
+
+/**
+ * Clears native (MatrixSyncService) tray notifications for a room after it is read.
+ * No-op when background sync / native Android is unavailable.
+ */
+export const clearNativeRoomNotifications = async (roomId: string): Promise<void> => {
+  if (!isBackgroundSyncSupported() || !roomId) return;
+
+  try {
+    await MatrixBackgroundSync.clearRoomNotifications({ roomId });
+  } catch (err) {
+    console.warn('[BackgroundSync] clearRoomNotifications failed:', err);
+  }
+};
+
+/**
+ * Syncs space/DM grouping metadata to the native layer for background notifications.
+ */
+export const syncNotificationGroupMap = async (
+  rooms: Record<
+    string,
+    { groupId: string; groupName: string; roomName: string; kind: string }
+  >
+): Promise<void> => {
+  if (!isBackgroundSyncSupported()) return;
+
+  try {
+    await MatrixBackgroundSync.setNotificationGroups({ rooms });
+  } catch (err) {
+    console.warn('[BackgroundSync] setNotificationGroups failed:', err);
+  }
+};

overlay/src/app/utils/tauri.ts

@@ -351,24 +351,7 @@ const ensureNotificationChannel = async (): Promise<void> => {
 };
 
 const ensureCapacitorNotificationChannel = async (): Promise<void> => {
-  if (notificationChannelCreated || !isAndroid()) return;
-
-  try {
-    const { LocalNotifications } = await import('@capacitor/local-notifications');
-    await LocalNotifications.createChannel({
-      id: 'messages',
-      name: 'Messages',
-      description: 'Message notifications from Matrix',
-      importance: 5,
-      sound: 'default',
-      visibility: 1,
-      vibration: true,
-      lights: true,
-    });
-    notificationChannelCreated = true;
-  } catch (err) {
-    console.warn('Failed to create Capacitor notification channel:', err);
-  }
+  await ensureCapacitorNotificationChannels();
 };
 
 /**
@@ -422,6 +405,225 @@ export const getSystemNotificationPermissionState = async (): Promise<Permission
   return 'denied';
 };
 
+/** Foreground sync status notification — must not collide with room message IDs. */
+const ANDROID_STATUS_NOTIFICATION_ID = 1001;
+
+/** Android notification group keys for rooms outside a space. */
+export const NOTIF_GROUP_DIRECTS = 'paarrot_directs';
+export const NOTIF_GROUP_HOME = 'paarrot_home';
+
+/** Capacitor / native channel ids (under the Paarrot app). */
+export const NOTIF_CHANNEL_DIRECTS = 'messages_directs';
+export const NOTIF_CHANNEL_SPACES = 'messages_spaces';
+export const NOTIF_CHANNEL_HOME = 'messages_home';
+/** Legacy channel — kept so older installs still receive. */
+export const NOTIF_CHANNEL_MESSAGES_LEGACY = 'messages';
+
+export type NotificationGroupKind = 'direct' | 'space' | 'home';
+
+export type NotificationGroupInfo = {
+  groupId: string;
+  groupName: string;
+  kind: NotificationGroupKind;
+  roomName?: string;
+};
+
+/**
+ * Stable Android notification id for a Matrix room.
+ * Re-using the same id replaces the previous tray entry instead of stacking.
+ */
+export const notificationIdForRoom = (roomId: string): number => {
+  let hash = 0;
+  for (let i = 0; i < roomId.length; i += 1) {
+    hash = (hash << 5) - hash + roomId.charCodeAt(i);
+    hash |= 0;
+  }
+  let id = Math.abs(hash) % 2147483647;
+  if (id === 0 || id === ANDROID_STATUS_NOTIFICATION_ID) {
+    id = ANDROID_STATUS_NOTIFICATION_ID + 1;
+  }
+  return id;
+};
+
+/** Stable id for a space/group summary notification. */
+export const notificationIdForGroupSummary = (groupId: string): number =>
+  notificationIdForRoom(`summary:${groupId}`);
+
+const channelIdForKind = (kind: NotificationGroupKind): string => {
+  switch (kind) {
+    case 'direct':
+      return NOTIF_CHANNEL_DIRECTS;
+    case 'space':
+      return NOTIF_CHANNEL_SPACES;
+    default:
+      return NOTIF_CHANNEL_HOME;
+  }
+};
+
+const ensureCapacitorNotificationChannels = async (): Promise<void> => {
+  if (!isAndroid()) return;
+
+  try {
+    const { LocalNotifications } = await import('@capacitor/local-notifications');
+    const channels: Array<{
+      id: string;
+      name: string;
+      description: string;
+    }> = [
+      {
+        id: NOTIF_CHANNEL_DIRECTS,
+        name: 'Direct messages',
+        description: 'One-to-one Matrix conversations',
+      },
+      {
+        id: NOTIF_CHANNEL_SPACES,
+        name: 'Spaces',
+        description: 'Messages from rooms inside Spaces',
+      },
+      {
+        id: NOTIF_CHANNEL_HOME,
+        name: 'Other rooms',
+        description: 'Rooms that are not in a Space',
+      },
+      {
+        id: NOTIF_CHANNEL_MESSAGES_LEGACY,
+        name: 'Messages',
+        description: 'Legacy message channel',
+      },
+    ];
+
+    await Promise.all(
+      channels.map((channel) =>
+        LocalNotifications.createChannel({
+          id: channel.id,
+          name: channel.name,
+          description: channel.description,
+          importance: 5,
+          sound: 'default',
+          visibility: 1,
+          vibration: true,
+          lights: true,
+        })
+      )
+    );
+    notificationChannelCreated = true;
+  } catch (err) {
+    console.warn('Failed to create Capacitor notification channels:', err);
+  }
+};
+
+const notificationBelongsToRoom = (
+  notification: { id?: number; extra?: Record<string, unknown> },
+  roomId: string
+): boolean => {
+  if (notification.id === notificationIdForRoom(roomId)) return true;
+  const extra = notification.extra;
+  if (!extra || typeof extra !== 'object') return false;
+  if (extra.roomId === roomId) return true;
+  const path = extra.path;
+  if (typeof path === 'string') {
+    return path.includes(encodeURIComponent(roomId)) || path.includes(roomId);
+  }
+  return false;
+};
+
+const clearCapacitorGroupSummaryIfEmpty = async (
+  LocalNotifications: {
+    getDeliveredNotifications: () => Promise<{ notifications: Array<{ id?: number; extra?: Record<string, unknown>; group?: string }> }>;
+    cancel: (opts: { notifications: Array<{ id: number }> }) => Promise<void>;
+    removeDeliveredNotifications: (opts: { notifications: unknown[] }) => Promise<void>;
+  },
+  groupId: string
+): Promise<void> => {
+  const summaryId = notificationIdForGroupSummary(groupId);
+  const delivered = await LocalNotifications.getDeliveredNotifications().catch(() => null);
+  if (!delivered?.notifications) return;
+
+  const siblings = delivered.notifications.filter((n) => {
+    if (n.id === summaryId) return false;
+    if (n.group === groupId) return true;
+    return n.extra?.groupId === groupId;
+  });
+
+  if (siblings.length > 0) return;
+
+  await LocalNotifications.cancel({ notifications: [{ id: summaryId }] }).catch(() => undefined);
+  const summary = delivered.notifications.find((n) => n.id === summaryId);
+  if (summary) {
+    await LocalNotifications.removeDeliveredNotifications({
+      notifications: [summary],
+    }).catch(() => undefined);
+  }
+};
+
+/**
+ * Dismiss system notifications tied to a room (after mark-as-read / receipt).
+ * Clears Capacitor LocalNotifications and native MatrixSyncService tray entries.
+ * Also drops the space/group summary when no child notifications remain.
+ */
+export const clearNotificationsForRoom = async (roomId: string): Promise<void> => {
+  if (!roomId) return;
+
+  if (isCapacitorNative()) {
+    try {
+      const { LocalNotifications } = await import('@capacitor/local-notifications');
+      const id = notificationIdForRoom(roomId);
+
+      const deliveredBefore = await LocalNotifications.getDeliveredNotifications().catch(() => null);
+      const roomNotif = deliveredBefore?.notifications?.find((n: { id?: number; extra?: Record<string, unknown> }) =>
+        notificationBelongsToRoom(n, roomId)
+      );
+      const groupId =
+        (typeof roomNotif?.extra?.groupId === 'string' && roomNotif.extra.groupId) ||
+        (typeof (roomNotif as { group?: string } | undefined)?.group === 'string'
+          ? (roomNotif as { group?: string }).group
+          : undefined);
+
+      await LocalNotifications.cancel({ notifications: [{ id }] }).catch(() => undefined);
+
+      if (deliveredBefore?.notifications?.length) {
+        const matching = deliveredBefore.notifications.filter((n: { id?: number; extra?: Record<string, unknown> }) =>
+          notificationBelongsToRoom(n, roomId)
+        );
+        if (matching.length > 0) {
+          await LocalNotifications.removeDeliveredNotifications({
+            notifications: matching,
+          }).catch(() => undefined);
+        }
+      }
+
+      if (groupId) {
+        await clearCapacitorGroupSummaryIfEmpty(LocalNotifications, groupId);
+      }
+    } catch (err) {
+      console.warn('Failed to clear Capacitor notifications for room:', err);
+    }
+
+    try {
+      const { clearNativeRoomNotifications } = await import('./backgroundSync');
+      await clearNativeRoomNotifications(roomId);
+    } catch (err) {
+      console.warn('Failed to clear native room notifications:', err);
+    }
+    return;
+  }
+
+  if (isTauri() && !isElectron()) {
+    try {
+      const { cancel, removeActive } = await import('@tauri-apps/plugin-notification');
+      const id = notificationIdForRoom(roomId);
+      if (typeof cancel === 'function') {
+        await cancel([id]).catch(() => undefined);
+      }
+      if (typeof removeActive === 'function') {
+        await removeActive([{ id }]).catch(() => undefined);
+      }
+    } catch (err) {
+      console.warn('Failed to clear Tauri notifications for room:', err);
+    }
+  }
+};
+
 /**
  * Send a notification using Tauri's notification plugin
  * Falls back to browser Notification API if not in Tauri
@@ -431,9 +633,20 @@ export const sendNotification = async (options: {
   body: string;
   icon?: string;
   path?: string;
+  roomId?: string;
+  group?: NotificationGroupInfo;
   onClick?: () => void;
 }): Promise<void> => {
-  const { title, body, icon, path, onClick } = options;
+  const { title, body, icon, path, roomId, group, onClick } = options;
+  const extra = {
+    ...(path ? { path } : {}),
+    ...(roomId ? { roomId } : {}),
+    ...(group?.groupId ? { groupId: group.groupId, groupName: group.groupName, groupKind: group.kind } : {}),
+  };
+  const hasExtra = Object.keys(extra).length > 0;
+  const channelId = group ? channelIdForKind(group.kind) : NOTIF_CHANNEL_HOME;
+  const groupId = group?.groupId;
+  const groupName = group?.groupName;
 
   // Use Electron's native notification API if in Electron
   if (isElectron()) {
@@ -475,11 +688,26 @@ export const sendNotification = async (options: {
         await tauriSendNotification({
           title,
           body,
+          // Stable per-room id replaces prior tray entry instead of stacking
+          id: roomId ? notificationIdForRoom(roomId) : undefined,
           // Use the channel on Android
-          channelId: isAndroid() ? 'messages' : undefined,
-          // Store path in extra data for notification tap handling
-          extra: path ? { path } : undefined,
+          channelId: isAndroid() ? channelId : undefined,
+          group: groupId,
+          // Store path/roomId in extra data for tap handling + clear-on-read
+          extra: hasExtra ? extra : undefined,
         });
+
+        if (isAndroid() && groupId && groupName) {
+          await tauriSendNotification({
+            title: groupName,
+            body: 'New messages',
+            id: notificationIdForGroupSummary(groupId),
+            channelId,
+            group: groupId,
+            groupSummary: true,
+            extra: { groupId, groupName, isGroupSummary: true },
+          }).catch(() => undefined);
+        }
       }
       return;
     } catch (err) {
@@ -496,21 +724,53 @@ export const sendNotification = async (options: {
       }
 
       if (perm.display === 'granted') {
-        await ensureCapacitorNotificationChannel();
+        await ensureCapacitorNotificationChannels();
+
+        // One notification per room: same id updates the existing tray entry.
+        const id = roomId
+          ? notificationIdForRoom(roomId)
+          : Math.floor(Date.now() % 2147483647);
+
+        const roomNotification: Record<string, unknown> = {
+          id,
+          title,
+          body,
+          channelId: isAndroid() ? channelId : undefined,
+          smallIcon: isAndroid() ? ANDROID_NOTIFICATION_SMALL_ICON : undefined,
+          iconColor: isAndroid() ? ANDROID_NOTIFICATION_ICON_COLOR : undefined,
+          extra: hasExtra ? extra : undefined,
+          threadIdentifier: groupId,
+        };
+
+        if (isAndroid() && groupId) {
+          roomNotification.group = groupId;
+          if (groupName) {
+            roomNotification.summaryText = groupName;
+          }
+          if (group?.roomName && group.roomName !== title) {
+            roomNotification.largeBody = body;
+          }
+        }
+
+        const notifications: Array<Record<string, unknown>> = [roomNotification];
+
+        // Nest rooms under a space / Directs / Home summary in the shade.
+        if (isAndroid() && groupId && groupName) {
+          notifications.push({
+            id: notificationIdForGroupSummary(groupId),
+            title: groupName,
+            body: 'New messages',
+            channelId,
+            smallIcon: ANDROID_NOTIFICATION_SMALL_ICON,
+            iconColor: ANDROID_NOTIFICATION_ICON_COLOR,
+            group: groupId,
+            groupSummary: true,
+            extra: { groupId, groupName, isGroupSummary: true },
+          });
+        }
 
-        const id = Math.floor(Date.now() % 2147483647);
         await LocalNotifications.schedule({
-          notifications: [
-            {
-              id,
-              title,
-              body,
-              channelId: isAndroid() ? 'messages' : undefined,
-              smallIcon: isAndroid() ? ANDROID_NOTIFICATION_SMALL_ICON : undefined,
-              iconColor: isAndroid() ? ANDROID_NOTIFICATION_ICON_COLOR : undefined,
-              extra: path ? { path } : undefined,
-            },
-          ],
+          notifications: notifications as any,
         });
       }
       return;