Remove the background audio keep-alive (App Review 2.5.4)

Apps/PointerLocker/BrowserViewController.swift

@@ -12,8 +12,7 @@ import WebKit
 ///  3. Hold Escape, ⌘., three-finger tap, app switch, navigation or the system
 ///     dropping the lock → page gets `pointerlockchange` and we release.
 ///
-/// The menu lives in +Menu, popups/dialogs/permissions in +WebUI, and the
-/// background keep-alive in BackgroundSessionKeeper.
+/// The menu lives in +Menu, popups/dialogs/permissions in +WebUI.
 final class BrowserViewController: UIViewController {
     private(set) var webView: WKWebView!
     /// Set by RootViewController; Settings uses it to switch services.
@@ -25,7 +24,6 @@ final class BrowserViewController: UIViewController {
     private var crashGuard = CrashLoopGuard()
     private var loadFailure: LoadFailure?
     private let network = NWPathMonitor()
-    private var sessionKeeper: BackgroundSessionKeeper!
     private var hudFeeder: DebugHUDFeeder!
     #if DEBUG
     private var debugBridge: DebugBridge?
@@ -77,7 +75,6 @@ final class BrowserViewController: UIViewController {
             webView.evaluateJavaScript(script) { _, _ in completion() }
         }
 
-        sessionKeeper = BackgroundSessionKeeper(webView: webView)
         hudFeeder = DebugHUDFeeder(webView: webView, bridge: bridge) { [weak self] in
             (self?.pageWantsLock ?? false, self?.isSystemPointerLocked ?? false)
         }
@@ -171,8 +168,11 @@ final class BrowserViewController: UIViewController {
     }
 
     /// Which phase the page's session is in (none / queued-loading / playing).
-    func sessionPhase(_ completion: @escaping (BackgroundSessionKeeper.StreamPhase) -> Void) {
-        sessionKeeper.currentPhase(completion)
+    func sessionPhase(_ completion: @escaping (StreamPhase) -> Void) {
+        guard let webView else { return completion(.none) }
+        webView.evaluateJavaScript(ServiceProfile.current.sessionPhaseScript) { result, _ in
+            completion(StreamPhase(rawValue: result as? Int ?? 0) ?? .none)
+        }
     }
 
     /// Before being replaced (service switch): stop listening to the mouse,
@@ -181,7 +181,6 @@ final class BrowserViewController: UIViewController {
         forceUnlock()
         bridge.invalidate()
         hudFeeder.stop()
-        sessionKeeper.willEnterForeground() // stops any keep-alive
         health.resetSession()
         #if DEBUG
         debugBridge?.stop()
@@ -248,11 +247,11 @@ final class BrowserViewController: UIViewController {
         observers.append(center.addObserver(forName: UIScene.willDeactivateNotification, object: nil, queue: .main) { [weak self] _ in
             self?.forceUnlock()
         })
+        // iPadOS suspends the app soon after it leaves the screen, which ends
+        // a game stream (docs/background-keep-alive.md has the keep-alive this
+        // replaced). Pause media now so nothing is cut off mid-sound.
         observers.append(center.addObserver(forName: UIScene.didEnterBackgroundNotification, object: nil, queue: .main) { [weak self] _ in
-            MainActor.assumeIsolated { self?.sessionKeeper.didEnterBackground() }
-        })
-        observers.append(center.addObserver(forName: UIScene.willEnterForegroundNotification, object: nil, queue: .main) { [weak self] _ in
-            MainActor.assumeIsolated { self?.sessionKeeper.willEnterForeground() }
+            MainActor.assumeIsolated { self?.webView?.pauseAllMediaPlayback() }
         })
     }
 

Apps/PointerLocker/Services/FigmaProfile.swift

@@ -14,7 +14,7 @@ extension ServiceProfile {
         // asks for the lock. Everything else it needs (WebGL 2, WebAssembly
         // SIMD, workers, OffscreenCanvas) is in WebKit.
         identity: .macChrome,
-        // No stream to keep alive; Figma saves as you go.
+        // No game session; Figma saves as you go.
         sessionPhaseScript: "0",
         tagline: "Collaborative design tool",
         artwork: ServiceArtwork(

Apps/PointerLocker/Services/ServiceCategory.swift

@@ -33,8 +33,8 @@ enum ServiceCategory: CaseIterable {
         }
     }
 
-    /// Games stream a session that must survive app switches (keep-alive,
-    /// voice chat); tools save as you go.
+    /// Games stream a session (switching services asks first, voice chat);
+    /// tools save as you go.
     var hasGameSession: Bool { self == .play }
 
     /// The services in this world, as a comma-separated list for Welcome.

Apps/PointerLocker/Services/ServiceProfile.swift

@@ -38,10 +38,18 @@ struct BrowserIdentity: Equatable {
     )
 }
 
+/// Where a service's session is, read from the page by `sessionPhaseScript`.
+/// A running session makes switching services ask first.
+enum StreamPhase: Int {
+    case none = 0     // library, sign-in, …
+    case starting = 1 // in the queue or loading the game
+    case playing = 2  // a stream is playing
+}
+
 /// Everything specific to one streaming service ("engine"): where it lives,
 /// which browser it needs to see, and how to tell that a session is running.
-/// The rest of the app (pointer lock, fullscreen emulation, mouse input,
-/// background keep-alive) is shared by all of them.
+/// The rest of the app (pointer lock, fullscreen emulation, mouse input) is
+/// shared by all of them.
 ///
 /// Adding a service: define a profile in its own file (see
 /// GeForceNowProfile.swift) and list it in `all`.
@@ -51,7 +59,7 @@ struct ServiceProfile {
     let homeURL: URL
     let identity: BrowserIdentity
     /// JavaScript evaluating to the session phase:
-    /// 0 none, 1 queued or loading, 2 streaming (see BackgroundSessionKeeper).
+    /// 0 none, 1 queued or loading, 2 streaming (see StreamPhase).
     let sessionPhaseScript: String
     /// One line under the name on the service card.
     let tagline: String

Apps/PointerLocker/Settings.swift

@@ -69,17 +69,6 @@ enum Settings {
         set { defaults.set(newValue.rawValue, forKey: "microphone") }
     }
 
-    /// How long a stream keeps running after the app goes to the background
-    /// (e.g. to answer a message), in seconds; 0 pauses it right away.
-    static var backgroundKeepAlive: TimeInterval {
-        get { defaults.object(forKey: "backgroundKeepAlive") as? TimeInterval ?? 300 }
-        set { defaults.set(newValue, forKey: "backgroundKeepAlive") }
-    }
-
-    static let backgroundKeepAlivePresets: [(title: String, seconds: TimeInterval)] = [
-        ("Off", 0), ("1 minute", 60), ("5 minutes", 300), ("15 minutes", 900),
-    ]
-
     /// Show the debug overlay (lock state, input, stream stats).
     static var debugHUD: Bool {
         get { defaults.bool(forKey: "debugHUD") }

Apps/PointerLocker/SettingsView.swift

@@ -13,7 +13,6 @@ struct SettingsView: View {
 
     @State private var sensitivity = Settings.sensitivity
     @State private var invertY = Settings.invertY
-    @State private var keepAlive = Settings.backgroundKeepAlive
     @State private var microphone = Settings.microphone
     @State private var useIdentity = Settings.useServiceIdentity
     @State private var debugHUD = Settings.debugHUD
@@ -45,16 +44,11 @@ struct SettingsView: View {
                 }
                 if service.category.hasGameSession {
                     Section {
-                        Picker("Keep game running in background", selection: $keepAlive) {
-                            ForEach(Settings.backgroundKeepAlivePresets, id: \.seconds) { Text($0.title).tag($0.seconds) }
-                        }
                         Picker("Microphone", selection: $microphone) {
                             ForEach(MicrophoneAccess.allCases, id: \.self) { Text($0.title).tag($0) }
                         }
                     } header: {
                         Text("Game session")
-                    } footer: {
-                        Text("Keeping the game running lets you switch apps briefly without losing your session.")
                     }
                 }
                 Section {
@@ -110,7 +104,6 @@ struct SettingsView: View {
         }
         .onChange(of: sensitivity) { Settings.sensitivity = sensitivity }
         .onChange(of: invertY) { Settings.invertY = invertY }
-        .onChange(of: keepAlive) { Settings.backgroundKeepAlive = keepAlive }
         .onChange(of: microphone) { Settings.microphone = microphone }
         .onChange(of: useIdentity) { Settings.useServiceIdentity = useIdentity }
         .onChange(of: debugHUD) { Settings.debugHUD = debugHUD }

README.md

@@ -128,19 +128,16 @@ NOW, Figma): pick one to switch straight to it. Each service reopens the page yo
 were last on, such as the open Figma file; a running game asks before you leave.
 Below that are Back, Reload, Home, Open URL and **Settings…**: switch service
 (with the setup guide), show the setup guide again, mouse sensitivity, invert
-Y-axis, background keep-alive, microphone, browser identity, the debug overlay,
+Y-axis, microphone, browser identity, the debug overlay,
 service checks, and About (version, links to the website and this
 repository). The button hides while the pointer is locked.
 
 **Switching apps mid-game.** iPadOS suspends an app within seconds of leaving
-it, which drops the stream and ends the session. Mouselook keeps itself
-running in the background during a session. While you wait in the queue or the
-game loads, it keeps running until the game starts, for up to 30 minutes. While
-a stream plays, it keeps running for 5 minutes by default (⋯ ▸ Settings… ▸ Keep game
-running in background: Off / 1 / 5 / 15 minutes). It does this by playing silence,
-since WebKit pauses a quiet stream in the background. When the time is up it
-pauses the stream so the system can suspend the app. GeForce NOW still needs a
-tap on Resume when you come back.
+it, which drops the stream, so leaving Mouselook mid-game can end the session.
+Mouselook pauses media when you leave. Earlier builds kept the app running in
+the background by playing silence; App Review doesn't allow that (guideline
+2.5.4), so it was removed. [docs/background-keep-alive.md](docs/background-keep-alive.md)
+has how it worked, in case it comes back in an allowed form.
 
 **Volume won't go to zero?** If you allowed the microphone, WebKit uses the
 voice-call audio mode, in which iPadOS keeps a minimum volume. Set ⋯ ▸ Settings… ▸
@@ -227,7 +224,6 @@ builds and tests the app.
 | `Resources/pointerlock-polyfill.js` | Pointer Lock and Fullscreen APIs in the page. It applies the profile's identity, including inside Web Workers, and turns native input into DOM events. |
 | `MouseBridge.swift` | Raw GCMouse input to the page, one batch per frame, never more than one in flight. |
 | `BrowserViewController*.swift` | The web view and lock state (+Menu, +WebUI for popups, dialogs and permissions). |
-| `BackgroundSessionKeeper.swift`, `BackgroundKeepAlive.swift` | Keeping a session alive across app switches. |
 | `PageRecovery.swift`, `StatusOverlayView.swift` | Crashes, failed loads and going offline. |
 | `DebugHUDFeeder.swift`, `Resources/debug-hud.js`, `DebugBridge.swift` | The debug overlay, and the Mac-side JavaScript console (Debug builds only). |