Background Tasks

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Request the system to launch your app in the background to run tasks using Background Tasks.

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BGContinuedProcessingTask does not work on the official release of iOS 26
The following code worked as expected on iOS 26 RC, but it no longer works on the official release of iOS 26. Is there something I need to change in order to make it work on the official version? Registration BGTaskScheduler.shared.register( forTaskWithIdentifier: taskIdentifier, using: nil ) { task in ////////////////////////////////////////////////////////////////////// // This closure is not called on the official release of iOS 26 ////////////////////////////////////////////////////////////////////// let task = task as! BGContinuedProcessingTask var shouldContinue = true task.expirationHandler = { shouldContinue = false } task.progress.totalUnitCount = 100 task.progress.completedUnitCount = 0 while shouldContinue { sleep(1) task.progress.completedUnitCount += 1 task.updateTitle("\(task.progress.completedUnitCount) / \(task.progress.totalUnitCount)", subtitle: "any subtitle") if task.progress.completedUnitCount == task.progress.totalUnitCount { break } } let completed = task.progress.completedUnitCount >= task.progress.totalUnitCount if completed { task.updateTitle("Completed", subtitle: "") } task.setTaskCompleted(success: completed) } Request let request = BGContinuedProcessingTaskRequest( identifier: taskIdentifier, title: "any title", subtitle: "any subtitle", ) request.strategy = .queue try BGTaskScheduler.shared.submit(request) Sample project code: https://github.com/HikaruSato/ExampleBackgroundProcess
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Sep ’25
Are iPad apps that are closed with the red traffic light prevented from running background tasks?
In iOS Background Execution limits, I see this: When the user ‘force quits’ an app by swiping up in the multitasking UI, iOS interprets that to mean that the user doesn’t want the app running at all. iOS also sets a flag that prevents the app from being launched in the background. That flag gets cleared when the user next launches the app manually. However, I see that when I close an app on iPadOS 26 with the red X, the app doesn't appear in the multitasking UI. So are they treated as force closes and prevented from running background tasks?
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Sep ’25
CallKit UI not invoked after receiving VoIP Push – app killed with NSInternalInconsistencyException
Our VoIP app receives PushKit notifications successfully (callservicesd Delivering 1 VoIP payload appears in logs). However, the app is consistently terminated by the system when running in the background or killed state. The crash is caused by iOS expecting a reportNewIncomingCall to CallKit, but the system reports: *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Killing app because it never posted an incoming call to the system after receiving a PushKit VoIP push.' *** Assertion failure in -[PKPushRegistry _terminateAppIfThereAreUnhandledVoIPPushes], PKPushRegistry.m:349 Key Observations: VoIP pushes arrive and are delivered to the app. In foreground, some methods work and CallKit UI sometimes appears. In background/killed state, app is always terminated before CallKit UI shows. Logs confirm the system requires CallKit to be reported immediately inside pushRegistry(_:didReceiveIncomingPushWith:for:completion:). Steps to Reproduce: Run the app with VoIP + CallKit integration. Put app in background (or kill it). Send a VoIP push. Observe system logs and crash: callservicesd: Delivering 1 VoIP payload(s) to application UrgiDoctor: Apps receiving VoIP pushes must post an incoming call via CallKit... error: Killing VoIP app because it failed to post an incoming call in time. Expected Behavior: On receiving a VoIP push, CallKit UI (Accept / Decline screen) should always appear. App should not be killed if reportNewIncomingCall is called in time. Actual Behavior: CallKit UI never appears in background/killed state. App is force-terminated by iOS before user can accept/decline the call. Request: Guidance on the correct sequence for calling reportNewIncomingCall and completionHandler() in pushRegistry. Clarification if any changes in iOS 17/18 affect PushKit + CallKit behavior. Best practices for ensuring CallKit UI always appears reliably after a VoIP push. Environment: iOS 18.5 Simulator + Device Xcode 16.4 Using PushKit + CallKit with VoIP entitlement
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Sep ’25
How can a Network Extension notify or trigger tasks in the main app when it’s backgrounded or killed?
I’m developing a iOS VPN app, and I need to execute a task in the main app even when it’s in the background or killed state. I know the Network Extension continues running during those times. Is there a way for the extension to immediately notify the app or trigger a task on the app side?
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Sep ’25
BGContinuedProcessingTask Notification Error
Hello im creating an expo module using this new API, but the problem i found currently testing this functionality is that when the task fails, the notification error doesn't go away and is always showing the failed task notification even if i start a new task and complete that one. I want to implement this module into the production app but i feel like having always the notification error might confuse our users or find it a bit bothersome. Is there a way for the users to remove this notification? Best regards!
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Sep ’25
App getting stuck after active from background
I got users feed back, sometimes they seem the launch screen after active from background, and the launch screen show more longer than the cold launch. I check the app's log, when this issue happens, it displays a view controller named 'STKPrewarmingViewController', and disappears after about 5 seconds. And form the normal users, app don't have same behavior. It seems app need prewarming after back from background, why? Devices System version: iOS 18.4, app build with Xcode 16. How to fixed this issues? Thanks!
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Sep ’25
WebRTC Data Channel for Background File Transfer Without Audio/Video
Hello, I’m building an iOS application that supports peer-to-peer file transfer. My goal is to use the WebRTC data channel only (no audio or video) to send files between users. I understand from Apple’s documentation that: • Apps are generally suspended in the background, and arbitrary sockets (like WebRTC) do not continue running. • Background file transfer is officially supported via URLSessionConfiguration.background, which the system manages reliably even if the app is suspended or terminated. • VoIP use cases require CallKit + audio/VoIP background modes, and CallKit must be used for legitimate calls (audio/video). What I want to confirm is: Is it supported for a WebRTC peer connection using only the data channel (no audio/video track, no CallKit call) to continue sending data when the app is in the background or locked? I considered using BGProcessingTask and BGAppRefreshTask, but as far as I can tell, those don’t allow maintaining long-lived sockets for active data transfer. Real-world developer discussions suggest that WebRTC connections are dropped when the app is backgrounded on iOS unless there’s at least one active audio track to keep the session alive. Can someone from Apple confirm if my understanding is correct—that data-only WebRTC connections will be killed in background unless they’re part of an active audio/video call with the appropriate entitlements? Thanks in advance!
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Sep ’25
BGTaskScheduler fails to match unique identifiers to a registered wildcard handler for BGContinuedProcessingTask
Testing Environment: iOS Version: 26.0 Beta 7 Xcode Version: 17.0 Beta 6 Device: iPhone 16 Pro Description: We are implementing the new BGContinuedProcessingTask API and are using the wildcard identifier notation as described in the official documentation. Our Info.plist is correctly configured with a permitted identifier pattern, such as com.our-bundle.export.*. We then register a single launch handler for this exact wildcard pattern. We are performing this registration within a UIViewController, which is a supported pattern as BGContinuedProcessingTask is explicitly exempt from the "register before applicationDidFinishLaunching" requirement, according to the BGTaskScheduler.h header file. The register method correctly returns true, indicating the registration was successful. However, when we then try to submit a task with a unique identifier that matches this pattern (e.g., com.our-bundle.export.UUID), the BGTaskScheduler.shared.submit() call throws an NSInternalInconsistencyException and terminates the app. The error reason is: 'No launch handler registered for task with identifier com.our-bundle.export.UUID'. This indicates that the system is not correctly matching the specific, unique identifier from the submit call to the registered wildcard pattern handler. This behavior contradicts the official documentation. Steps to Reproduce: Create a new Xcode project. In Signing & Capabilities, add "Background Modes" (with "Background processing" checked) and "Background GPU Access". Add a permitted identifier (e.g., "com.company.test.*") to BGTaskSchedulerPermittedIdentifiers in Info.plist. In a UIViewController's viewDidLoad, register a handler for the wildcard pattern. Check that the register method returns true. Immediately after, try to submit a BGContinuedProcessingTaskRequest with a unique identifier that matches the pattern. Expected Results: The submit call should succeed without crashing, and the task should be scheduled. Actual Results: The app crashes immediately upon calling submit(). The console shows an uncaught NSInternalInconsistencyException with the reason: 'No launch handler registered for task with identifier com.company.test.UUID'. Workaround: The issue can be bypassed if we register a new handler for each unique identifier immediately before submitting a request with that same unique identifier. This strongly suggests the bug is in the system's wildcard pattern-matching logic.
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Sep ’25
Inquiry Regarding Background HTTP Service Support in iOS
Dear Apple App Store Review Team, We are currently developing an application focused on user data asset management, aimed at helping users better protect and manage their personal data. One of the core features of our application is to allow users to access files stored on their mobile devices from other devices within the same local network. At present, our implementation works as follows: once the application is launched, it starts an HTTP service in the background to support access from other devices within the local network. However, we have encountered a technical challenge in the iOS environment: when the application is moved to the background or the device screen is turned off, the system imposes strict limitations on the runtime of background tasks. Our testing has shown that, typically after about 30 seconds, the background HTTP service is suspended by the system, which prevents other devices from continuing to access the files. As developers, we would like to clarify the following: What specific technical steps are required to enable a continuous background HTTP service under iOS? During development, which aspects (e.g., system permission configurations, App Store review guidelines) need to be addressed to support such functionality? What qualifications or requirements (e.g., entitlement requests, compliance documentation) are necessary for an application to provide unrestricted HTTP service in the background? If such behavior is not officially supported, we kindly request that you provide the relevant official guidelines and documentation so that we can fully understand the applicable policies and requirements. Thank you very much for your time and guidance.
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Sep ’25
Should ModelActor be used to populate a view?
I'm working with SwiftData and SwiftUI and it's not clear to me if it is good practice to have a @ModelActor directly populate a SwiftUI view. For example when having to combine manual lab results and clinial results from HealthKit. The Clinical lab results are an async operation: @ModelActor actor LabResultsManager { func fetchLabResultsWithHealthKit() async throws -> [LabResultDto] { let manualEntries = try modelContext.fetch(FetchDescriptor<LabResult>()) let clinicalLabs = (try? await HealthKitService.getLabResults()) ?? [] return (manualEntries + clinicalLabs).sorted { $0.date > $1.date }.map { return LabResultDto(from: $0) } } } struct ContentView: View { @State private var labResults: [LabResultDto] = [] var body: some View { List(labResults, id: \.id) { result in VStack(alignment: .leading) { Text(result.testName) Text(result.date, style: .date) } } .task { do { let labManager = LabResultsManager() labResults = try await labManager.fetchLabResultsWithHealthKit() } catch { // Handle error } } } } EDIT: I have a few views that would want to use these labResults so I need an implementation that can be reused. Having to fetch and combine in each view will not be good practice. Can I pass a modelContext to a viewModel?
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Aug ’25
HealthKit Background Delivery and URLSession.shared.dataTask
Hello. I have implemented background delivery for detecting changes in health kit with HKObserverQuery. It works well, I am reading changes. And I am sending this changes to an https endpoint with using an URLSession.shared.dataTask inside the HKObserverQuery callback while my app is terminated. I have several questions about this: Is starting a URLSession.shared.dataTask inside HKObserverQuery callback when app is terminated is correct way to do it? I am calling HKObserverQuery completion handler whatever dataTask returned success or failure but I am wondering what if the network connection is low and this dataTask response could not received in 2-3 seconds. I have read background deliveries should take 1-2 seconds. Should I use an URL session with background configuration for sending those HTTPS requests? If so, should I use download task or upload task (they don't fit my requirements I am sending a simple json)?
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Aug ’25
Health Kit Background Delivery and URLSession.shared.dataTask
Hello. I have implemented background delivery for detecting changes in health kit with HKObserverQuery. It works well, I am reading changes. And I am sending this changes to an https endpoint with using an URLSession.shared.dataTask inside the HKObserverQuery callback while my app is terminated. I have several questions about this: Is starting a URLSession.shared.dataTask inside HKObserverQuery callback is correct way to do it? I am calling HKObserverQuery completion handler whatever dataTask returned success or failure but I am wondering what if the network connection is low and this dataTask response could not received in 2-3 seconds. I have read HealthKit background deliveries should take 1-2 seconds. Should I use background task somehow for sending those HTTPS requests?
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Aug ’25
App is getting terminated by OS even after calling BG task expiration
The application is placed into the idle state. Subsequently, the device enters a sleep state. While the device is in sleep, App start background task within the application successfully receives its expirationHandler callback. App received the expiration callback and App called the end BGtask OS did not released the Assertion. Resulting in App getting terminated by the OS for exceeding the BG task Apple Feedback- FB19192371
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Aug ’25
BGContinuedProcessingTask compatibility with background URLSession
My app does really large uploads. Like several GB. We use the AWS SDK to upload to S3. It seemed like using BGContinuedProcessingTask to complete a set of uploads for a particular item may improve UX as well as performance and reliability. When I tried to get BGContinuedProcessingTask working with the AWS SDK I found that the task would fail after maybe 30 seconds. It looked like this was because the app stopped receiving updates from the AWS upload and the task wants consistent updates. The AWS SDK always uses a background URLSession and this is not configurable. I understand the background URLSession runs in a separate process from the app and maybe that is why progress updates did not continue when the app was in the background. Is it expected that BGContinuedProcessingTask and background URLSession are not really compatible? It would not be shocking since they are 2 separate background APIs. Would the Apple recommendation be to use a normal URLSession for this, in which case AWS would need to change their SDK? Or does Apple think that BGContinuedProcessingTask should just not be used with uploads? In other words use an upload specific API. Thanks!
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Aug ’25
Testing and Debugging Code Running in the Background
I regularly bump into folks confused by this issue, so I thought I’d collect my thoughts on the topic into a single (hopefully) coherent post. If you have questions or comments, put them in a new thread here on the forums. Feel free to use whatever subtopic and tags that apply to your situation, but make sure to add the Debugging tag so that I see your thread go by. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" Testing and Debugging Code Running in the Background I regularly see questions like this: My background code works just fine in Xcode but fails when I download the app from the App Store. or this: … or fails when I run my app from the Home screen. or this: How do I step through my background code? These suggest a fundamental misunderstanding of how the debugger interacts with iOS’s background execution model. The goal of this post is to explain that misunderstanding so that you can effectively test and debug background code. Note The focus of this post is iOS. The advice here generally applies to any of iOS’s ‘child’ platforms, so iPadOS, tvOS, and so on. However, there will be some platform specific differences, especially on watchOS. This advice here doesn’t apply to macOS. It’s background execution model is completely different than the one used by iOS. Understand the Fundamentals The key point to note here is that the debugger prevents your app from suspending. This has important consequences for iOS’s background execution model. Normally: iOS suspends your app when it’s in the background. Once your app is suspended, it becomes eligible for termination. The most common reason for this is that the system wants to recover memory, but it can happen for various other reasons. For example, the system might terminate a suspended app in order to update it. Under various circumstances your app can continue running after moving to the background. A great example of this is the continued processed task feature, introduced in iOS 26 beta. Alternatively, your app can be resumed or relaunched in the background to perform some task. For example, the region monitor feature of Core Location can resume or relaunch your app in the background when the user enters or leaves a region. If no app needs to be executing, the system can sleep the CPU. None of this happens in the normal way if the debugger is attached to your app, and it’s vital that you take that into account when debugging code that runs in the background. An Example of the Problem For an example of how this can cause problems, imagine an app that uses an URLSession background session. A background session will resume or relaunch your app in the background when specific events happen. This involves two separate code paths: If your app is suspended, the session resumes it in the background. If your app is terminated, it relaunches it in the background. Neither code path behaves normally if the debugger is attached. In the first case, the app never suspends, so the resume case isn’t properly exercised. Rather, your background session acts like it would if your app were in the foreground. Normally this doesn’t cause too many problems, so this isn’t a huge concern. On the other hand, the second case is much more problematic. The debugger prevents your app from suspending, and hence from terminating, and thus you can’t exercise this code path at all. Seek Framework-Specific Advice The above is just an example, and there are likely other things to keep in mind when debugging background code for a specific framework. Consult the documentation for the framework you’re working with to see if it has specific advice. Note For URLSession background sessions, check out Testing Background Session Code. The rest of this post focuses on the general case, offering advice that applies to all frameworks that support background execution. Run Your App Outside of Xcode When debugging background execution, launch your app from the Home screen. For day-to-day development: Run the app from Xcode in the normal way (Product > Run). Stop it. Run it again from the Home screen. Alternatively, install a build from TestFlight. This accurately replicates the App Store install experience. Write Code with Debugging in Mind It’s obvious that, if you run the app without attaching the debugger, you won’t be able to use the debugger to debug it. Rather: Extract the core logic of your code into libraries, and then write extensive unit tests for those libraries. You’ll be able to debug these unit tests with the debugger. Add log points to help debug your integration with the system. Treat your logging as a feature of your product. Carefully consider where to add log points and at what level to log. Check this logging code into your source code repository and ship it — or at least the bulk of it — as part of your final product. This logging will be super helpful when it comes to debugging problems that only show up in the field. My general advice is that you use the system log for these log points. See Your Friend the System Log for lots of advice on that front. One of the great features of the system log is that disabled log points are very cheap. In most cases it’s fine to leave these in your final product. Attach and Detach In some cases it really is helpful to debug with the debugger. One option here is to attach to your running app, debug a specific thing, and then detach from it. Specifically: To attach to a running app, choose Debug > Attach to Process > YourAppName in Xcode. To detach, choose Debug > Detach. Understand Force Quit iOS allows users to remove an app from the multitasking UI. This is commonly known as force quit, but that’s not a particularly accurate term: The multitasking UI doesn’t show apps that are running, it shows apps that have been run by the user. The UI shows recently run apps regardless of whether they’re in the foreground, running in the background, suspended, or terminated. So, removing an app from the UI may not actually quit anything. Removing an app sets a flag that prevents the app from being launched in the background. That flag gets cleared when the user next launches the app manually. Note In some circumstances iOS will not honour this flag. The exact cases where this happens are not documented and have changed over time. Keep these behaviours in mind as you debug your background execution code. For example, imagine you’re trying to test the URLSession background relaunch code path discussed above. If you force quit your app, you’ll never hit this code path because iOS won’t relaunch your app in the background. Rather, add a debug-only button that causes your app to call exit. IMPORTANT This suggestion is for debugging only. Don’t include a Quit button in your final app! This is specifically proscribed by QA1561. Alternatively, if you’re attached to your app with Xcode, simply choose Product > Stop. This is like calling exit; it has no impact on your app’s ability to run in the background. Test With Various Background App Refresh Settings iOS puts users in control of background execution via the options in Settings > General > Background App Refresh. Test how your app performs with the following settings: Background app refresh turned off overall Background app refresh turned on in general but turned off for your app Background app refresh turned on in general and turned on for your app IMPORTANT While these settings are labelled Background App Refresh, they affect subsystems other than background app refresh. Test all of these cases regardless of what specific background execution feature you’re using. Test Realistic User Scenarios In many cases you won’t be able to fully test background execution code at your desk. Rather, install a TestFlight build of your app and then use the device as a normal user would. For example: To test Core Location background execution properly, actual leave your office and move around as a user might. To test background app refresh, use your app regularly during the day and then put your device on charge at night. Testing like this requires two things: Patience Good logging The system log may be sufficient here, but you might need to investigate other logging solutions that are more appropriate for your product. These testing challenges are why it’s critical that you have unit tests to exercise your core logic. It takes a lot of time to run integration tests like this, so you want to focus on integration issues. Before starting your integration tests, make sure that your unit tests have flushed out any bugs in your core logic. Revision History 2025-08-12 Made various editorial changes. 2025-08-11 First posted.
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Aug ’25
[iOS 26 beta] UIScene migration with loadFileURL:allowingReadAccessToURL: has partial rendering for app BG launch
We're currently migrating from AppDelegate to UISceneDelegate due to console warnings . Our application's UI, which is built on a single webpage, functions correctly when launched in the foreground after this migration. However, we've encountered an issue with partial rendered UI components when launching the application from the background, such as upon receiving a VoIP call. During a background launch, the following delegate calls occur before the client attempts to load a local webpage: [08/07 16:25:49:037][ 0x101ea3910]<ALA_SIGNAL>: [OS-PLT] Exit -[AppDelegate application:didFinishLaunchingWithOptions:] [08/07 16:25:49:084][ 0x10c0c4140]<PushToTalk> [Pushnotif] [] <ALA_SIGNAL>: [OS-CCF] Enter -[PushNotificationManager pushRegistry:didReceiveIncomingPushWithPayload:forType:withCompletionHandler:] [08/07 16:25:49:098][ 0x101ea3910]Begin -[SceneDelegate scene:willConnectToSession:options:] [08/07 16:25:49:098][ 0x101ea3910]Exit -[SceneDelegate scene:willConnectToSession:options:] As part of client login process we load the index page in WebKit here: [08/07 16:25:50:977][ 0x101ea3910]<ALA_SIGNAL>: [PLT-OS] Enter -[SceneDelegate loadUI:] [UI Launch Reason = 1] Code: NSString *path = [[NSBundle mainBundle]pathForResource:@"index" ofType:@"html" inDirectory:@"www"]; NSURL *urlReq = [NSURL fileURLWithPath:path]; [webView loadFileURL:urlReq allowingReadAccessToURL:urlReq]; The problem we're observing is that the webpage is only partially rendering in this background launch scenario (Seen after brought to FG). Any insights or assistance you can provide would be greatly appreciated.
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Aug ’25
Background Modes, ScreenTime API
I’m attempting to run Apple’s ScreenTime API while my app is in the background When debugging on a device my background restrictions functionality works, but on TestFlight it does not. This is the error message when analyzing the device in XCodes Console BackgroundTaskSuspended. Background entitlement: NO When the proper entitlements are added this error doesn't allow for the build to be uploaded to TestFlight. Provisioning profile "iOS Team Provisioning Profile: com.xxx.xxx" doesn't include the UIBackgroundModes entitlement. I have the proper entries in the “Signing and Capabilities” of the project, but my functionality will not run in the background when the app is not launched. I just need a function to run that calls Apple's ScreenTime API while my app is in the background. Other apps have achieved the functionality I’m looking for so I know it’s possible, but this is the roadblock I’m running into.
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Aug ’25
Problem receiving Remote Notification in the background after Review Rejected
I created an app. One if its functionalities is receive Remote Notification in the background, while app is monitoring Significant Location Changes (SLC). This functionality worked fine. I was receiving these notifications correctly. Sometimes instantly, sometime with small or large delay. And then I send the app for review. It was rejected with 3 remarks: The app or metadata includes information about third-party platforms that may not be relevant for App Store users, who are focused on experiences offered by the app itself (I wrote that app communication works both for iOS and Android.) The app declares support for audio in the UIBackgroundModes key in your Info.plist but we are unable to locate any features that require persistent audio. EULA (End User License Agreement) is missing for in-app purchases. After the rejection the app is no longer receiving these notifications. They are there, since the app receives them, when I open app, or significant location change is detected. It also works, when I run the app directly from Xcode (in debug mode), not from TestFlight nor in Sandbox. It seem to me like Apple somehow spoiled my background capabilities on purpose or accidentally. Is it possible? What can I do with it? Is it the case that I should just fix the review remarks and send the app back to review, and once the app passes it, it will work again? Or should I not count on it? Any suggestions? I asked Apple using: https://developer.apple.com/contact/topic/#!/topic/select but so far no response.
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Aug ’25
Reliable 30-minute background data fetching for safety-critical monitoring app?
I'm developing a safety-critical monitoring app that needs to fetch data from government APIs every 30 minutes and trigger emergency audio alerts for threshold violations. The app must work reliably in background since users depend on it for safety alerts even while sleeping. Main Challenge: iOS background limitations seem to prevent consistent 30-minute intervals. Standard BGTaskScheduler and timers get suspended after a few minutes in background. Question: What's the most reliable approach to ensure consistent 30-minute background monitoring for a safety-critical app where missed alerts could have serious consequences? Are there special entitlements or frameworks for emergency/safety applications? The app needs to function like an alarm clock - working reliably even when backgrounded with emergency audio override capabilities.
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Jul ’25