Hi, I have a watchOS app that records audio for an extended period of time and because the mic is active, continues to record in background mode when the watch face is off. However, when a call comes in or Siri is activated, recording stops because of an audio interruption. Here is my code for setting up the session: private func setupAudioSession() { let audioSession = AVAudioSession.sharedInstance() do { try audioSession.setCategory(.playAndRecord, mode: .default, options: [.overrideMutedMicrophoneInterruption]) try audioSession.setActive(true, options: .notifyOthersOnDeactivation) } catch { print("Audio Session error: \(error)") } } Before this I register an interruption handler that holds a reference to my AudioEngine (which I start and stop each time recording is activated by the user): _audioInterruptionHandler = AudioInterruptionHandler(audioEngine: _audioEngine) And here is how this class implements recovery: fileprivate class AudioInterruptionHandler { private let _audioEngine: AVAudioEngine public init(audioEngine: AVAudioEngine) { _audioEngine = audioEngine // Listen to interrupt notifications NotificationCenter.default.addObserver(self, selector: #selector(handleAudioInterruption(notification:)), name: AVAudioSession.interruptionNotification, object: nil) } @objc private func handleAudioInterruption(notification: Notification) { guard let userInfo = notification.userInfo, let interruptionTypeRawValue = userInfo[AVAudioSessionInterruptionTypeKey] as? UInt, let interruptionType = AVAudioSession.InterruptionType(rawValue: interruptionTypeRawValue) else { return } switch interruptionType { case .began: print("[AudioInterruptionHandler] Interruption began") case .ended: print("[AudioInterruptionHandler] Interruption ended") print("Interruption ended") do { try AVAudioSession.sharedInstance().setActive(true) } catch { print("[AudioInterruptionHandler] Error resuming audio session: \(error.localizedDescription)") } default: print("[AudioInterruptionHandler] Unknown interruption: \(interruptionType.rawValue)") } } } Unfortunately, it fails with: Error resuming audio session: Session activation failed Is this even possible to do on watchOS? This code worked for me on iOS. Thank you, -- B.

Hi all, My application requires to create a WebSocket server on an iOS application for other devices can connect and transfer data with my application. I used Vapor library to create a socket server and it works well when the application is in the foreground. I am trying to keep the server alive when my app moves to the background or the suspended state so that my app and other devices can continue to communicate with each other. Is there any ways to achieve that? I tried to turn on a mode: "Audio, Airplay, and Picture in Picture" in background modes section in Signing & Capabilities and then my application can still communicate with clients when it is background mode. But my application is an application for user can edit image and send it to other devices through sockets and it does not have audio, airplay,.. feature. Is it ok to publish the app to the app store in the future? Thank you!

Hello, I have an app that receives critical alarms. This is usually done through remote push notifications from the server, but to add redundancy I'd like to add a MQTT connection as well. There are scenarios where internet connection might be missing (but there is a local WiFi connection to the server) hence I'd like to deliver the alarms directly from server to client without going out via the Internet. The problem is that according to all restrictions on iOS, the MQTT connection will not be maintained in the background and disconnect occurs within 20-30 sec after going in the background and shutting the screen. I'm aware of all the background modes that iOS allows but none fall within this scenario. Is there a way to maintain a MQTT connection (or some other type of network connection) in the background on iOS?

Hello, I'm developing a voice communication App using Livekit SDK. Everything works fine in the foreground, AudioSession is activated and audio transmitted. However, I would like to add a feature, I would like my app to receive audio even when it's in background or terminated. I know I can run code when the App is in that state by sending a background push notification, but the only thing that is not working in that case is the AudioSession activation. It fails with error "Session activation failed", no more clues. I tried every combination of category and mode, but no success. Bacground modes in XCode have been activated: -Audio, AirPlay, and Picture in Picture -Background Processing Is this a limit of Livekit? I would be grateful if someone can point me into the right direction.

Can't we set up a network server that constantly runs in the background, even in the applications we will develop for corporate companies? @eskimo

hi I recently developed an iOS APP which will advertise in background, as I checked the developer document, device name and service uuid will be ignored when iOS APP goes to background. But I found an APP named Berkanan which can broadcast in backgound with device name and service uuid, and its device name length exceeds 8 bytes, does anyone know how it implements? thanks!

We have been using the BGTask (specifically a BGProcessingTask) reliably for the last couple of years for our app. Up until now they wake up automatically while the screen is off, the iPad is plugged in, and the app is running (that is, in the background), but never while the screen is on (that is, never when the scenePhase == .active). For the last month or so, I've noticed that they are triggering now while the screen is displayed. How is this possible??? Did something change with a recent version of iOS? It's violating Apple's own documentation, which describes the BGProcessingTask as: "A time-consuming processing task that runs while the app is in the background."

I'm working on a app that can communicate, send and receive data from our own MFi scanner. Ideally, this app can receives data and remains communication even when it's in background, but I can only runs a background task for maximum 30 sec. Along with this main app, we also have a keyboard extension as an interface that can publish collected data to other app that user prefers with string format. However, It seems like Apple doesn't allow to implement UIApplication.shared.beginBackgroundTask method in extension class, is there any alternative that worth to try? Also, can I extend app background task time elapsed to at least 30 minutes? If I can get an official response would be great!

My App keeps crashing in the background and I don't know why. I'm using SwiftData and SwiftUI. I'm setting up a .backgroundTask like this: import SwiftUI import SwiftData import TipKit @main struct MyAppName: App { @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate @State var navManager = NavigationManager.load() @State var alerter: Alerter = Alerter() var sharedModelContainer: ModelContainer = { do { return try ModelContainer(for: DataController.schema, configurations: [DataController.modelConfig]) } catch { fatalError("Could not create ModelContainer: \(error)") } }() var body: some Scene { WindowGroup { SetupView() .accentColor(.myAccentColor) .environment(alerter) .alert(isPresented: $alerter.isShowingAlert) { alerter.alert ?? Alert(title: Text(verbatim: "")) } .task { try? Tips.configure([ .displayFrequency(.immediate), .datastoreLocation(.applicationDefault) ]) } .onAppear { setUpAppDelegate() } } .modelContainer(sharedModelContainer) .backgroundTask(.appRefresh(Const.backgroundAppRefreshId)) { @MainActor in let container = sharedModelContainer await RefreshManager.handleBackgroundVideoRefresh(container) } .environment(navManager) } func setUpAppDelegate() { appDelegate.navManager = navManager } } The RefreshManager.handleBackgroundRefresh(...) goes on to load data and then insert models for them via SwiftData. It only happens occasionally and afaik only in the background. Weirdly enough the issue seems to be there even when I only print something in the background task. Even when I don't schedule/set a background task at all. How can that be? The crashes started in the version that included the .backgroundTask, although perhaps it's related to something else. I'm still trying to further narrow it down. This is the crash report that I'm getting: Exception Type: EXC_BREAKPOINT (SIGTRAP) Exception Codes: 0x0000000000000001, 0x00000001a1bb98c0 Termination Reason: SIGNAL 5 Trace/BPT trap: 5 Terminating Process: exc handler [809] Triggered by Thread: 0 Thread 0 name: Thread 0 Crashed: 0 libswiftCore.dylib 0x00000001a1bb98c0 _assertionFailure(_:_:file:line:flags:) + 264 (AssertCommon.swift:144) 1 libswiftCore.dylib 0x00000001a1c27d14 swift_unexpectedError + 664 (ErrorType.swift:188) 2 _SwiftData_SwiftUI 0x000000024310cd78 one-time initialization function for empty + 300 (ModelContainer+Extensions.swift:5) 3 libdispatch.dylib 0x00000001ab16add4 _dispatch_client_callout + 20 (object.m:576) 4 libdispatch.dylib 0x00000001ab16c654 _dispatch_once_callout + 32 (once.c:52) 5 _SwiftData_SwiftUI 0x000000024310cdf8 one-time initialization function for empty + 124 (ModelContainer+Extensions.swift:12) 6 libdispatch.dylib 0x00000001ab16add4 _dispatch_client_callout + 20 (object.m:576) 7 libdispatch.dylib 0x00000001ab16c654 _dispatch_once_callout + 32 (once.c:52) 8 _SwiftData_SwiftUI 0x0000000243122170 key path getter for EnvironmentValues.modelContext : EnvironmentValues + 140 (<compiler-generated>:0) 9 libswiftCore.dylib 0x00000001a1ce4628 RawKeyPathComponent._projectReadOnly<A, B, C>(_:to:endingWith:) + 1012 (KeyPath.swift:1701) 10 libswiftCore.dylib 0x00000001a1ce3ddc KeyPath._projectReadOnly(from:) + 1036 (KeyPath.swift:331) 11 libswiftCore.dylib 0x00000001a1ce8348 swift_getAtKeyPath + 24 (KeyPath.swift:2029) 12 SwiftUI 0x00000001a7af4814 EnvironmentBox.update(property:phase:) + 872 (Environment.swift:273) 13 SwiftUI 0x00000001a782a074 static BoxVTable.update(ptr:property:phase:) + 396 (DynamicPropertyBuffer.swift:294) 14 SwiftUI 0x00000001a78297b0 _DynamicPropertyBuffer.update(container:phase:) + 104 (DynamicPropertyBuffer.swift:215) 15 SwiftUI 0x00000001a887fb78 closure #1 in closure #1 in DynamicBody.updateValue() + 104 (DynamicProperty.swift:447) 16 SwiftUI 0x00000001a887fbb8 partial apply for closure #1 in closure #1 in DynamicBody.updateValue() + 28 (<compiler-generated>:0) 17 libswiftCore.dylib 0x00000001a1bcc068 withUnsafeMutablePointer<A, B>(to:_:) + 28 (LifetimeManager.swift:82) 18 SwiftUI 0x00000001a887f9dc closure #1 in DynamicBody.updateValue() + 408 (DynamicProperty.swift:446) 19 SwiftUI 0x00000001a887f5c0 DynamicBody.updateValue() + 712 (DynamicProperty.swift:445) 20 SwiftUI 0x00000001a71e8bf8 partial apply for implicit closure #1 in closure #1 in closure #1 in Attribute.init<A>(_:) + 32 (<compiler-generated>:0) 21 AttributeGraph 0x00000001cbd4c240 AG::Graph::UpdateStack::update() + 512 (ag-graph-update.cc:578) 22 AttributeGraph 0x00000001cbd42f38 AG::Graph::update_attribute(AG::data::ptr<AG::Node>, unsigned int) + 424 (ag-graph-update.cc:719) 23 AttributeGraph 0x00000001cbd42810 AG::Graph::input_value_ref_slow(AG::data::ptr<AG::Node>, AG::AttributeID, unsigned int, unsigned int, AGSwiftMetadata const*, unsigned char&, long) + 720 (ag-graph.cc:1429) 24 AttributeGraph 0x00000001cbd423a4 AGGraphGetValue + 228 (AGGraph.mm:701) 25 SwiftUI 0x00000001a887f548 DynamicBody.updateValue() + 592 (DynamicProperty.swift:444) 26 SwiftUI 0x00000001a71e8bf8 partial apply for implicit closure #1 in closure #1 in closure #1 in Attribute.init<A>(_:) + 32 (<compiler-generated>:0) 27 AttributeGraph 0x00000001cbd4c240 AG::Graph::UpdateStack::update() + 512 (ag-graph-update.cc:578) 28 AttributeGraph 0x00000001cbd42f38 AG::Graph::update_attribute(AG::data::ptr<AG::Node>, unsigned int) + 424 (ag-graph-update.cc:719) [...] 107 SwiftUI 0x00000001a7cf79fc static App.main() + 132 (App.swift:114) 108 MyAppName 0x0000000100e6d120 static MyAppNameApp.$main() + 52 (MyAppNameApp.swift:0) 109 MyAppName 0x0000000100e6d120 main + 64 110 dyld 0x00000001c67c2d84 start + 2240 (dyldMain.cpp:1298) The report also says key path getter for EnvironmentValues.modelContext, which seems odd. Any idea where I could start to look for the issue? I'm currently just trying things out, pushing them to TestFlight and waiting for crashes to happen. As soon as I can narrow it down further I'll update this.

XCode 15.3, watchOS 10.4 SDK Our health-related app is exploring adding an additional feature that would make use of extended runtime sessions to guide users through an activity. A user starts a session by tapping a button on the watchOS app's interface. If a session is already running, pressing that button should cause the current session to invalidate, and a new session should be created so we can start again from the beginning. TLDR: Running new sessions works as expected on the simulator but not on a real device. Why? We currently have a barebones implementation that includes logging in the extended runtime session delegate functions, on the button push, and when the new session is about to start. Here's what our logging output for the simulator looks like when we try to invalidate the current session and run another one: Invalidating extended session Optional("<WKExtendedRuntimeSession: 0x60000262d7a0> state=2, sessionID=4894EB1D-96F7-4921-8263-378E304E719F, expirationDate=2024-03-20 13:01:10 +0000") at 12:01:21 PM Extended runtime session <WKExtendedRuntimeSession: 0x60000262d7a0> state=3, sessionID=4894EB1D-96F7-4921-8263-378E304E719F, expirationDate=2024-03-20 13:01:10 +0000 invalidated for reason WKExtendedRuntimeSessionInvalidationReason(rawValue: 0) with error nil at 12:01:21 PM Requesting new extended session in application state 0 at 12:01:22 PM Starting new extended session Optional("<WKExtendedRuntimeSession: 0x600002644540> state=0, sessionID=B34ECCFF-A0DA-45C1-9FD1-FD0F335FBE02, expirationDate=(null)") in application state 0 at 12:01:23 PM Did start extended session <WKExtendedRuntimeSession: 0x600002644540> state=2, sessionID=B34ECCFF-A0DA-45C1-9FD1-FD0F335FBE02, expirationDate=2024-03-20 13:01:23 +0000 at 12:01:23 PM As you can see, we successfully invalidate a running session, a button press requests a new one, and then we create and start a new runtime session instance which ends in the running (2) state. We can repeat this over and over without issue. The exact same code running on an actual device produces this: Invalidating extended session Optional(\"<WKExtendedRuntimeSession: 0x15db5750> state=2, sessionID=889FE2E8-0FDA-4826-9094-4D48094FEBED, expirationDate=2024-03-20 12:53:55 +0000\") at 11:56:04AM Extended runtime session <WKExtendedRuntimeSession: 0x15db5750> state=3, sessionID=889FE2E8-0FDA-4826-9094-4D48094FEBED, expirationDate=2024-03-20 12:53:55 +0000 invalidated for reason WKExtendedRuntimeSessionInvalidationReason(rawValue: 0) with error nil at 11:56:04AM Requesting new extended session in application state 0 at 11:56:05AM Starting new extended session Optional(\"<WKExtendedRuntimeSession: 0x15e0aba0> state=0, sessionID=D5020337-D20B-48BE-B2EE-EE44BE580AEC, expirationDate=(null)\") in application state 0 at 11:56:06AM Extended runtime session <WKExtendedRuntimeSession: 0x15e0aba0> state=3, sessionID=D5020337-D20B-48BE-B2EE-EE44BE580AEC, expirationDate=(null) invalidated for reason WKExtendedRuntimeSessionInvalidationReason(rawValue: 1) with error nil at 11:56:06AM The difference is in the last line: starting the session was unsuccessful and it was immediately invalidated, with the reason WKExtendedRuntimeSessionInvalidationReason(rawValue: 1) which maps to the enum sessionInProgress. This is surprising, since we just invalidated and dereferenced the old runtime session. What else can we do to tear down this session? In fact, no other extended runtime sessions can be created and started successfully until the device is rebooted. One note is that on the simulator we do get the following warning right after invalidating the running session: -[WKExtendedRuntimeSession _invalidateWithError:]_block_invoke_2:527: Got error Error Domain=com.apple.CarouselServices.SessionErrorDomain Code=3 "Session not running <CSLSession: 0x600003b4eca0; pid: 8833; dismissed: NO; ended: YES; duration: 3600.0; autoEnd: NO; launchable: NO; mutuallyExclusive: YES; managed: YES; persisted: NO; requiresFGActiveInitiation: YES; lastForeground: 2024-03-20 12:01:21 +0000> |CSLSSession = { | sessionID: 4894EB1D-96F7-4921-8263-378E304E719F; bundleID: com.bundle; type: "physical therapy"; running: NO; paused: NO; expirationDate: 2024-03-20 13:01:10 +0000; supportsAOT: NO; lastStartWasScheduled: NO; remote: NO; |}" UserInfo={NSLocalizedDescription=Session not running <CSLSession: 0x600003b4eca0; pid: 8833; dismissed: NO; ended: YES; duration: 3600.0; autoEnd: NO; launchable: NO; mutuallyExclusive: YES; managed: YES; persisted: NO; requiresFGActiveInitiation: YES; lastForeground: 2024-03-20 12:01:21 +0000> |CSLSSession = { | sessionID: 4894EB1D-96F7-4921-8263-378E304E719F; bundleID: com.bundle; type: "physical therapy"; running: NO; paused: NO; expirationDate: 2024-03-20 13:01:10 +0000; supportsAOT: NO; lastStartWasScheduled: NO; remote: NO; |}} This appears to be thrown by some part of Carousel, for which no public documentation exists, and it clearly doesn't disrupt the expected behavior on the simulator. I don't know if this is being thrown on the device, since our logging wouldn't be able to pick it up. Please let me know if we are approaching this incorrectly or if there are any known solutions to this issue.

My background audio app stops updating its Live Activity after the iPhone locks, and doesn't resume updating the activity after tapping the screen or even after FaceID unlocks the device (without opening the lock screen). My live activity requests a ContentState update & iOS updates the content for the activity as below: Task{ log.debug("LiveActivityManager.updateLiveActivity() with new ContentState") await liveActivity.update( ActivityContent(state:contentState, staleDate:nil) ) } Below what my log looks like: <<<<SWIPE LOCK SCREEN DOWN>>>> DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState iOS: Updating content for activity 0A519263-1E46-4BB6-BA4F-F3DDBC081AB4 DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState iOS: Updating content for activity 0A519263-1E46-4BB6-BA4F-F3DDBC081AB4 <<<<PRESS LOCK BUTTON->Lock iPhone>>>> INFO: --------protectedDataWillBecomeUnavailableNotification-------- DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState iOS: Updating content for activity 0A519263-1E46-4BB6-BA4F-F3DDBC081AB4 DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState <<<<LOOK AT & TAP LOCK SCREEN->Unlock iPhone without swiping up>>>> INFO: --------protectedDataDidBecomeAvailableNotification----------- DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState DEBUG: LiveActivityManager.updateLiveActivity() with new ContentState As shown in the log, normally iOS updates the content for my activity after my liveActivity.update request. This works fine in the Dynamic Island and when after switching apps and swiping down to see the lock screen without locking the phone. However, once I lock the phone, iOS stops updating the Live Activity content, and doesn't resume updates until after the app regains the foreground at least once. Has anyone else encountered this behavior? Is this a setting that I'm missing, or a bug?

I want to update my live activity every X minutes but it is not working while app in background mode and app going background mode to suspend mode after some time automatically How can i update my live activity every X minutes using background Task.

I'm working on a screen where the goal is for the user to walk for 6 minutes while the app times them and measures the distance walked. I'm using CMPedometer to track the walking distance and a repeating 1-second Timer to count down the time. This works fine as long as the app is in the foreground, but I'd like my user to be able to lock their phone and put it away while they walk. I used UIApplication.shared.beginBackgroundTask, but it doesn't provide enough time. It usually only gives me around 30 seconds. I also tried calling UIApplication.shared.beginBackgroundTask again or calling it once every time the timer ticks, with no better result. How can I accomplish my goal here?

We are developing a SwiftUI iOS app which behaves as a client to a MJPEG server on a local network. This means that our app should read images sent from a special hardware we are developing using HTTP protocol. The testing is working fine, but our concern is that when the app goes to the background or the phone is locked, the HTTP connection gets closed after one minute. However, we need to have this HTTP connection alive all the time because we are developing a safety monitoring app that should continue its monitoring state even when the phone is locked. We are constantly running object detection AI algorithm on the transferred images from the hardware. Is there a solution to our concern. Could we have example code to a solution?

Is there a possibility to develop an iOS app that is connected to an external camera connected through lightning or USB-C port and receives video stream. We need to be able to get this video stream even while the app is in the background or if the phone is locked. We could have the camera connected wirelessly through the lightning port. Is there an available library or a sample app featuring such functionalities. Thanks.

I have an app which uses Cocoa Pods to use MQTTClient in connecting to io.adafruit. I use the app to get the various data point stored at io.adafruit and to even send data to adafruit to control a connected unit. I am using .xcworkspace to upload the app on my phone and everything works fine. I am hoping to wake my app every so ofter to get some data points from io.adafruit and if certain conditions exist, I want to send a notification to the user. I have added Background Modes to my app's Signing & Capabilities (Background fetch) and in my INFO I have Permitted background task scheduler identifiers with the String identifier LEVELIT.Refresh. The following is my code I am using in my AppDelegate.h #import <UIKit/UIKit.h> #import <CoreData/CoreData.h> #import <MQTTClient/MQTTClient.h> #import <UserNotifications/UserNotifications.h> @interface AppDelegate: UIResponder <UIApplicationDelegate, UNUserNotificationCenterDelegate,UIAlertViewDelegate,MQTTSessionDelegate>{ MQTTSession *session3; } @property (nonatomic, retain) MQTTSession *session3; @property (nonatomic, strong) NSPersistentContainer *persistentContainer; @end And this is the code I use in my AppDelegate.m #import "AppDelegate.h" #import <BackgroundTasks/BackgroundTasks.h> #import <CloudKit/CloudKit.h> #import <UserNotifications/UserNotifications.h> static NSString* TaskID = @"LEVELIT.refresh"; @interface AppDelegate() @property (nonatomic, retain) NSString *myUserName; @property (nonatomic, retain) NSString *myUserKey; @property (nonatomic, retain) NSString *myTrips; @property (nonatomic, retain) NSString *atrip; @property (nonatomic, retain) NSString *trip; @property (nonatomic, retain) NSString *gettrip; @property(strong) void (^expirationHandler)(void); @end @implementation AppDelegate @synthesize session3,window; - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { if (@available(iOS 13.0, *)) { [[BGTaskScheduler sharedScheduler] registerForTaskWithIdentifier:TaskID usingQueue:nil launchHandler:^(BGAppRefreshTask *task) { [self handleAppRefreshTask:task]; }]; } else { // Fallback on earlier versions } UNUserNotificationCenter* center = [UNUserNotificationCenter currentNotificationCenter]; [center requestAuthorizationWithOptions:(UNAuthorizationOptionAlert + UNAuthorizationOptionSound) completionHandler:^(BOOL granted, NSError * _Nullable error) { }]; UNNotificationCategory* generalCategory = [UNNotificationCategory categoryWithIdentifier:@"GENERAL" actions:@[] intentIdentifiers:@[] options:UNNotificationCategoryOptionCustomDismissAction]; NSUserDefaults *defaults2 = [NSUserDefaults standardUserDefaults]; if([[[defaults2 dictionaryRepresentation] allKeys] containsObject:@"myUserNameFile"]){ NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults]; self.myUserName = [defaults objectForKey:@"myUserNameFile"]; NSLog(@"myUserName1:%@",self.myUserName); self.myUserKey = [defaults objectForKey:@"myUserKeyFile"]; NSLog(@"myUserKey1:%@",self.myUserKey); } return YES; } } -(void)schedualLocalNotifications{ } - (void)setTaskCompletedWithSuccess:(BOOL)success;{ NSLog(@"Completed"); } - (void)applicationDidEnterBackground:(UIApplication *)application { NSLog(@"Entering background"); if (@available(iOS 13.0, *)) { BGAppRefreshTaskRequest *request = [[BGAppRefreshTaskRequest alloc] initWithIdentifier:TaskID]; request.earliestBeginDate = [NSDate dateWithTimeIntervalSinceNow:15*60]; NSError *error; BOOL success = [[BGTaskScheduler sharedScheduler] submitTaskRequest:request error:&error]; if (success == TRUE) { } } //BREAKPOINT } -(void)handleAppRefreshTask:(BGAppRefreshTask *)task API_AVAILABLE(ios(13.0)){ //do things with task NSLog(@"Process started!"); task.expirationHandler = ^{ NSLog(@"WARNING: expired before finish was executed."); }; MQTTCFSocketTransport *transport = [[MQTTCFSocketTransport alloc] init]; transport.host = @"io.adafruit.com"; transport.port = 1883; self.session3 = [[MQTTSession alloc] init]; self.session3.userName = self.myUserName; self.session3.password = self.myUserKey; self.session3.transport = transport; self.session3.delegate = self; self.session3.keepAliveInterval = 30; // new stuff NSString *feeds = [self.myUserName stringByAppendingString:@"/feeds/"]; self.atrip = [feeds stringByAppendingString:@"trip"]; self.gettrip = [self.atrip stringByAppendingString:@"/get"]; [session3 connectWithConnectHandler:^(NSError *error) { if(!error){ [self.session3 subscribeToTopic:self.atrip atLevel:1 subscribeHandler:^(NSError *error, NSArray *gQoss){ if (error) { NSLog(@"Subscription failed %@", error.localizedDescription); } else { NSLog(@"Subscription sucessfull! Granted Qos: %@", gQoss); NSData* data = [@"0" dataUsingEncoding:NSUTF8StringEncoding]; [self.session3 publishData:data onTopic:self.gettrip retain:NO qos:0 publishHandler:nil]; } }]; dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(45* NSEC_PER_SEC)), dispatch_get_main_queue(), ^{ [task setTaskCompletedWithSuccess:YES]; }); self.session3.keepAliveInterval =30; } else {NSLog(@"[connectWithConnectHandler]Error Connect %@", error.localizedDescription);} }]; task.expirationHandler = ^{ NSLog(@"WARNING: expired before finish was executed."); }; } } } //More code here but too much. @end I am not sure about the local notification because the BGAppRefreshTask is not working. I have placed a breakpoint just after the app enters background and the TASK is submitted. Then I type in e -l objc -- (void)[[BGTaskScheduler sharedScheduler] _simulateLaunchForTaskWithIdentifier:@"LEVELIT.refresh"] The app launches in the background but I get an error error: Header search couldn't locate module MQTTClient error: couldn't install checkers, unknown error Message from debugger: Terminated due to signal 9 When I tried running the app without .xcworkspace the project said it couldn't find MQTTClient. But with the workspace everything works fine. Why would launching the app in the background cause the app not to locate the MQTTClient libraries? And how do I work around this problem? Any and all help would be appreciated.

Currently working on an emergency app paired with a BLE device, and the desired use case is: When the device is triggered, it sends your location to your emergency contacts an API we've built. This flow works while the app is open, but we need things to obviously work while in background (while the phone is sleeping as well, of course, for emergency contexts) From what I've researched and understood, background fetches don't really work, because the intervals are a maximum of about 15 minutes, and iOS will make them less frequent based on app usage, and that window in an emergency situation isn't good enough. Having read around, I've bumped into a couple resources that suggest background bluetooth processing is possible, if I listen for a particular service being advertised, but I haven't been able to make things work so far. I wanted some help on this.

Hi, I'm relatively new to iOS development and kindly ask for some feedback on a strategy to achieve this desired behavior in my app. My Question: What would be the best strategy for sound effect playback when an app is in the background with precise timing? Is this even possible? Context: I created a basic countdown timer app (targeting iOS 17 with Swift/SwiftUI.). Countdown sessions can last up to 30-60 mins. When the timer is started it progresses through a series of sub-intervals and plays a short sound for each one. I used AVAudioPlayer and everything works fine when the app is in the foreground. I'm considering switching to AVAudioEngine b/c precise timing is very important and the AIs tell me this would have better precision. I'm already setting "App plays audio or streams audio/video using AirPlay" in my Plist, and have configured: AVAudioSession.sharedInstance().setCategory(.playback, mode: .default, options: .mixWithOthers) Curiously, when testing on my iPhone 13 mini, sounds sometimes still play when the app is in the background, but not always. What I've considered: Background Tasks: Would they make any sense for this use-case? Seems like not if the allowed time is short &amp; limited by the system. Pre-scheduling all Sounds: Not sure this would even work and seems like a lot of memory would be needed (could be hundreds of intervals). ActivityKit Alerts: works but with a ~50ms delay which is too long for my purposes. Pre-Render all SFX to 1 large audio file: Seems like a lot of work and processing time and probably not worth it. I hope there's a better solution. I'd really appreciate any feedback.

I have an app to communicate with a peripheral via L2CAP channel. Even I already enabled "Uses Bluetooth LE accessories" in "Background Mode", it still stop working when I lock the screen. Did some search and found these two posts: CBL2CAPChannel not responsive while app is backgrounded iOS Swift CoreBluetooth CBL2CAPChannel L2CAP Channel Oriented Connection Cannot Reconnect After Close From Central I am wondering if there are any solutions or work around about this. Based on the use case, I prefer to use L2CAP to transfer large data between two devices, so won't consider GATT.

I'm trying to execute a background task following the Developer Documentation. This is my code import SwiftUI @main struct MyAppTest_Watch_AppApp: App { @Environment(\.scenePhase) var scenePhase let bs = BackgroundSession() @SceneBuilder var body: some Scene { WindowGroup { ContentView() }.backgroundTask(.appRefresh("prova")) { context in print("bg task") await scheduleTask() } .onChange(of: scenePhase) { phase in switch phase { case .active: print("\(#function) REPORTS - App change of scenePhase to ACTIVE") case .inactive: print("\(#function) REPORTS - App change of scenePhase Inactive") case .background: print("\(#function) REPORTS - App change of scenePhase Background") WKApplication.shared() .scheduleBackgroundRefresh( withPreferredDate: Date.init(timeIntervalSinceNow: 5 * 60.0), userInfo: "prova" as NSSecureCoding & NSObjectProtocol, scheduledCompletion: schedule) default: print("\(#function) REPORTS - App change of scenePhase Default") } } } func scheduleTask() async { bs.testSession() await WKApplication.shared() .scheduleBackgroundRefresh( withPreferredDate: Date.init(timeIntervalSinceNow: 5 * 60.0), userInfo: "prova" as NSSecureCoding & NSObjectProtocol, scheduledCompletion: schedule) } func schedule(error: Error?) { if error != nil { // Handle the scheduling error. fatalError("*** An error occurred while scheduling the background refresh task. ***") } print("Scheduled!") } } On the simulator the background refresh occurs correctly according to the preferred date and executes the background task, on the real watch it does not. I also set the app as complication in my watch face. The device I'm testing the app on is an Apple Watch Serie 7 with watchOS 10.3. Any idea?