On macOS Tahoe26.0, iOS 26.0 (23A5287g), Xcode 26.0 beta 3 (17A5276g) 1、Follow this tutorial Downloading asset packs hosted by Apple When i download a background asset packs hosted by Apple, Xcode callback "Download failed: The helper received an invalid server response with the status code “400”." Before downloading, I uploaded the three aar files to the Apple server using the Transporter app. Three Manifest.json content is： {"assetPackID":"bdassets2","downloadPolicy":{"onDemand":{}},"fileSelectors":[{"file":"1.jpg"},{"file":"2.pag"},{"file":"3.mp4"}],"platforms":["iOS"]} and {"assetPackID":"bdassets1","downloadPolicy":{"prefetch":{"installationEventTypes":["firstInstallation","subsequentUpdate"]}},"fileSelectors":[{"file":"1.jpg"},{"file":"2.pag"},{"file":"3.mp4"},{"directory":"a1"}],"platforms":["iOS"]} and {"assetPackID":"bdassets0","downloadPolicy":{"essential":{"installationEventTypes":["firstInstallation","subsequentUpdate"]}},"fileSelectors":[{"file":"1.jpg"},{"file":"2.pag"},{"file":"3.mp4"},{"directory":"a1"}],"platforms":["iOS"]} The same error was reported when the three aar files were obtained. I obtained it using the following code: do {       let assetPack = try await AssetPackManager.shared.assetPack(withID: "bdassets2")       try await AssetPackManager.shared.ensureLocalAvailability(of: assetPack)     } catch {       print("Download failed:", error)     } 2、Follow this tutorial Testing your asset packs locally I use this command line to start the test server：xcrun ba-serve --host 172.17.9.62 bdassets2.aar, The content displayed on the terminal is： Loading asset packs… Loading the asset pack at “bdassets2.aar”… Choose an identity in the panel to continue. Listening on port 56061… When running the project, Xcode reports an error:Download failed: Could not connect to the server. I use iPhone directly visit this website: https://172.17.9.62:56061, on the page display "Hello, world!" There are too few error messages in both of the above questions. I have no idea what the specific reasons are.I hope someone can offer some guidance. Best Regards.

Hi, I'm working on a VisionOS app and would like to integrate Background Assets to download large files after the app is installed. I'm wondering what would happen if the user takes off the headset while a background asset is being downloaded. Would it continue downloading or would the download be stopped/paused? I was looking for a way to download large assets while the user is not wearing the Vision Pro, is there any other alternative? Thanks in advance.

Hi, I have some questions regarding the Background Assets Extension and DeviceCheck framework. Goal: Ensure that only users who have purchased the app can access the server's API without any user authentication using for example DeviceCheck framework and within a Background Assets Extension. My app relies on external assets, which I'm loading using the Background Assets Extension. I'm trying to determine if it's possible to obtain a challenge from the server and send a DeviceCheck assertion during this process within the Background Assets Extension. So far, I only receive session-wide authentication challenges—specifically NSURLAuthenticationMethodServerTrust in the Background Assets Extensio. I’ve tested with Basic Auth (NSURLAuthenticationMethodHTTPBasic) just for experimentation, but the delegate func backgroundDownload( _ download: BADownload, didReceive challenge: URLAuthenticationChallenge ) async -> (URLSession.AuthChallengeDisposition, URLCredential?) is never called with that authentication method. It seems task-specific challenges aren't coming through at all. Also, while the DCAppAttestService API appears to be available on macOS, DCAppAttestService.isSupported always returns false (in my testing), which suggests it's not actually supported on macOS. Can anyone confirm if that’s expected behavior?

Hi. I have a device that is connected to my phone and sends few bytes at different times. The app caches those events and sends them to server as soon as internet is available. This all works, but when app goes to background or user locks the phone then after few seconds app has no internet access. It still caches the events that are important but unable to send them until app is brought to foreground. How can app still connect to server? I saw few posts saying they solved it by using URLSession with a background mode, but in my case it says: Terminating app due to uncaught exception 'NSGenericException', reason: 'Upload tasks from NSData are not supported in background sessions.' As I understood URLSession can download or upload files, but the events comming from BLE device are few bytes, so how to send them to server as soon as possible? Found this stackoverflow question and gave me some hopes https://stackoverflow.com/questions/63016680/sending-network-request-after-bluetooth-update-while-ios-app-is-in-background but no examples at all.

If new photo is added to library and app is not running in foreground or was not opened after the new photo was added but the app is having full access to gallery, can it access, read the new photo - If the app is not specifically a cloud syncing app, can it have this attached function, suppose it is a game app or beauty camera app?

We are using AVAssetDownloadURLSession to download content with multiple audio tracks. Still, we are facing an issue where only one audio language is being downloaded, despite explicitly requesting multiple audio languages. However, all subtitle variants are being downloaded successfully. Issue Details: Observed Behaviour: When initiating a download using AVAssetDownloadURLSession, only one audio track (Hindi, in this case) is downloaded, even though the content contains multiple audio tracks. Expected Behaviour: All requested audio tracks should be downloaded, similar to how subtitle variants are successfully downloaded. Please find sample app implementation details: https://drive.google.com/file/d/1DLcBGNnuWFYsY0cipzxpIHqZYUDJujmN/view?usp=sharing Manifest file for the asset looks something like below #EXTM3U #EXT-X-VERSION:6 #EXT-X-INDEPENDENT-SEGMENTS #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="A1",NAME="Hindi",LANGUAGE="hi",URI="indexHindi/Hindi.m3u8",AUTOSELECT=YES,DEFAULT=YES #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="A2",NAME="Bengali",LANGUAGE="bn",URI="indexBengali/Bengali.m3u8",AUTOSELECT=YES,DEFAULT=YES #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="A3",NAME="Kannada",LANGUAGE="kn",URI="indexKannada/Kannada.m3u8",AUTOSELECT=YES,DEFAULT=YES #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="A4",NAME="Malayalam",LANGUAGE="ml",URI="indexMalayalam/Malayalam.m3u8",AUTOSELECT=YES,DEFAULT=YES #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="A5",NAME="Tamil",LANGUAGE="ta",URI="indexTamil/Tamil.m3u8",AUTOSELECT=YES,DEFAULT=YES #EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="A6",NAME="Telugu",LANGUAGE="te",URI="indexTelugu/Telugu.m3u8",AUTOSELECT=YES,DEFAULT=YES #EXT-X-STREAM-INF:BANDWIDTH=832196,AVERAGE-BANDWIDTH=432950,RESOLUTION=640x360,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A1",SUBTITLES="subs" index-4k360p/360p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=832196,AVERAGE-BANDWIDTH=432950,RESOLUTION=640x360,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A2",SUBTITLES="subs" index-4k360p/360p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=832196,AVERAGE-BANDWIDTH=432950,RESOLUTION=640x360,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A3",SUBTITLES="subs" index-4k360p/360p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=832196,AVERAGE-BANDWIDTH=432950,RESOLUTION=640x360,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A4",SUBTITLES="subs" index-4k360p/360p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=832196,AVERAGE-BANDWIDTH=432950,RESOLUTION=640x360,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A5",SUBTITLES="subs" index-4k360p/360p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=832196,AVERAGE-BANDWIDTH=432950,RESOLUTION=640x360,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A6",SUBTITLES="subs" index-4k360p/360p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1317051,AVERAGE-BANDWIDTH=607343,RESOLUTION=854x480,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A1",SUBTITLES="subs" index-4k480p/480p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1317051,AVERAGE-BANDWIDTH=607343,RESOLUTION=854x480,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A2",SUBTITLES="subs" index-4k480p/480p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1317051,AVERAGE-BANDWIDTH=607343,RESOLUTION=854x480,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A3",SUBTITLES="subs" index-4k480p/480p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1317051,AVERAGE-BANDWIDTH=607343,RESOLUTION=854x480,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A4",SUBTITLES="subs" index-4k480p/480p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1317051,AVERAGE-BANDWIDTH=607343,RESOLUTION=854x480,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A5",SUBTITLES="subs" index-4k480p/480p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1317051,AVERAGE-BANDWIDTH=607343,RESOLUTION=854x480,FRAME-RATE=25.0,CODECS="hvc1.2.4.L93.b0,mp4a.40.2",AUDIO="A6",SUBTITLES="subs" index-4k480p/480p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1715498,AVERAGE-BANDWIDTH=717018,RESOLUTION=1024x576,FRAME-RATE=25.0,CODECS="hvc1.2.4.L123.b0,mp4a.40.2",AUDIO="A1",SUBTITLES="subs" index-4k576p/576p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1715498,AVERAGE-BANDWIDTH=717018,RESOLUTION=1024x576,FRAME-RATE=25.0,CODECS="hvc1.2.4.L123.b0,mp4a.40.2",AUDIO="A2",SUBTITLES="subs" index-4k576p/576p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1715498,AVERAGE-BANDWIDTH=717018,RESOLUTION=1024x576,FRAME-RATE=25.0,CODECS="hvc1.2.4.L123.b0,mp4a.40.2",AUDIO="A3",SUBTITLES="subs" index-4k576p/576p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1715498,AVERAGE-BANDWIDTH=717018,RESOLUTION=1024x576,FRAME-RATE=25.0,CODECS="hvc1.2.4.L123.b0,mp4a.40.2",AUDIO="A4",SUBTITLES="subs" index-4k576p/576p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1715498,AVERAGE-BANDWIDTH=717018,RESOLUTION=1024x576,FRAME-RATE=25.0,CODECS="hvc1.2.4.L123.b0,mp4a.40.2",AUDIO="A5",SUBTITLES="subs" index-4k576p/576p.m3u8 #EXT-X-STREAM-INF:BANDWIDTH=1715498,AVERAGE-BANDWIDTH=717018,RESOLUTION=1024x576,FRAME-RATE=25.0,CODECS="hvc1.2.4.L123.b0,mp4a.40.2",AUDIO="A6",SUBTITLES="subs" index-4k576p/576p.m3u8 #EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID="subs",NAME="English",DEFAULT=YES,AUTOSELECT=YES,FORCED=NO,LANGUAGE="en",URI="subtitle_en/sub_en_vtt.m3u8"

Any idea to achieve reliable periodic Bluetooth data retrieval on iOS, even when the app is closed or killed.

**Hi everyone ** We try to add BackgroundAssetExtension to our project, in local testing work fine, but when we try upload app to TestFlight we get some errors that we don't know how to fix. App Supported Destinations: iPhone, iPad, Mac(Designed for iPad) Minimum Deployments: iOS 12 BackgroundAssetExtension Minimum Deployments: iOS 16.4 Error when try to upload to TestFlight: "<IDEDistributionIssue: severity(error), error(Error Domain=ContentDelivery Code=90171 \"Asset validation failed\" UserInfo={IDEDistributionIssueSeverity=3, NSLocalizedDescription=Asset validation failed, NSLocalizedRecoverySuggestion=Invalid bundle structure. The \U201cDemo.app/decompressed_data_5.bin\U201d binary file is not permitted. Your app cannot contain standalone executables or libraries, other than a valid CFBundleExecutable of supported bundles. For details, visit: https://developer.apple.com/documentation/bundleresources/placing_content_in_a_bundle (ID: 3dfe207a-b4e5-43db-9464-fcf59a730545)})>", "<IDEDistributionIssue: severity(error), error(Error Domain=ContentDelivery Code=90924 \"Asset validation failed\" UserInfo={IDEDistributionIssueSeverity=3, NSLocalizedDescription=Asset validation failed, NSLocalizedRecoverySuggestion=Invalid Info.plist value. (ID: 073b5957-2e5b-4a7b-a4ae-7735b30a2d05)})>" when we checked archive (Show package contents) that many files like compressed_data_1.bin compressed_data_2.bin compressed_data_3.bin compressed_data_4.bin compressed_data_5.bin compressed_data_6.bin decompressed_data_1.bin decompressed_data_2.bin decompressed_data_3.bin decompressed_data_4.bin decompressed_data_5.bin decompressed_data_6.bin We added to main target in Build Phase -> Embed ExtensionKit Extensions Info.plist <key>BAEssentialMaxInstallSize</key> <integer>3250188</integer> <key>BAInitialDownloadRestrictions</key> <dict> <key>BADownloadAllowance</key> <integer>3250188</integer> <key>BADownloadDomainAllowList</key> <array> <string>*</string> <string>*</string> </array> <key>BAEssentialDownloadAllowance</key> <integer>3250188</integer> </dict> <key>BAManifestURL</key> <string>https://*/itemsmeta</string> <key>BAMaxInstallSize</key> <integer>3250188</integer> We will be appreciate for any suggestions :) If need some additional information let me know :pray:

Hi everyone, We came an issue that, In some scenarios in our app we cannot fetch any resources from device (Photo and Contact). One case we catched is putting app in background and spending time in other commonly used apps and coming back to our app cause this issue but there is a small chance that get this issue during using the application. In cell, we are trying to fetch the image like this imageFetchTask = Task { let image = await CompositionRoot.shared.photosManager.image(requestType: .imageCollections, forId: photoAsset.photoId) self.photoImageView.image(image) } and inner layers of this code we get the PHAsset and request image PHAsset.firstAsset(for: id) let manager = PHImageManager.default() manager.requestImage(for: asset, targetSize: request.targetSize, contentMode: .aspectFill, options: request.options) { (image, info) in continuation.resume(returning: image) } We figured out that issue not happening only in Photos also Contacts and any web request. So any help according to this situation is well appreciated. Thanks

DeviceActivityReport presents statistics for a device: https://developer.apple.com/documentation/deviceactivity/deviceactivityreport The problem: DeviceActivityReport can present statistics with a delay for a parent device (when DeviceActivityReport is presenting, the DeviceActivityReportExtension is called to process the statistics). One possible solution is to call DeviceActivityReport periodically throughout the day in a child device. However, the app will not be available all day. Is there any way to run DeviceActivityReport in the background? I have tried the following approach, but it didn’t work (DeviceActivityReportExtension didnt call): let hostingController: UIHostingController? = .init(rootView: DeviceActivityReport(context, filter: filter)) hostingController?.view.frame = .init(origin: .zero, size: .init(width: 100, height: 100)) hostingController?.beginAppearanceTransition(true, animated: false) hostingController?.loadView() hostingController?.viewDidLoad() try? await Task.sleep(for: .seconds(0.5)) hostingController?.viewWillAppear(true) hostingController?.viewWillLayoutSubviews() try? await Task.sleep(for: .seconds(0.5)) hostingController?.viewDidAppear(true) try? await Task.sleep(for: .seconds(0.5)) hostingController?.didMove(toParent: rootVC) try? await Task.sleep(for: .seconds(0.5)) hostingController?.viewWillLayoutSubviews() hostingController?.viewDidLayoutSubviews() hostingController?.view.layoutIfNeeded() hostingController?.view.layoutSubviews() hostingController?.endAppearanceTransition() Is there any way to run DeviceActivityReport in the background? (when app is not visible/closed). The main problem is call DeviceActivityReport

The background asset keys (BAEssentiaMaxInstallSize/BAMaxInstallSize) referenced in the app's Info.plist will be displayed to users on the App Store, as outlined in the WWDC video and supported by Apple’s documentation. Could you please clarify where exactly on the App Store's product page these values will be visible? Is the size displayed on the App Store a sum of the app bundle size and the size specified in these keys within the Info.plist?

Hi, I'm implementing a BADownloaderExtension in my app for essential assets. I would like to treat the install case differently than the update case, however it seems whether I "install" or "update" the app (via TestFlight) I always end up getting a BAContentRequest of type .install. I can simulate an update via xcrun, but cannot seem to get into that case in the wild. Is this expected?

My app is able to receive data updates when it is in foreground. however, when i move it in background then sync engine stops syncing until I again move app to foreground.

Hi Ty for playing

I want to download some large files on watchOS and I found Apple Music app is able to download songs in background and pause downloading depending on battery life. Does there any way to do the same thing in my own app? After users choose to download, keep the downloading task in background and pause/resume on demand.

I am having an issue with scheduling daily background task (eg: nightly) when app is in terminated app state (user forcefully terminated the app from app switcher). If the app is in suspended state, I am able to schedule a daily background task. But is there a way to wake up the app nightly and register a BGTask when user forcefully terminates the app.

The app declares support for Voice-over IP (VoIP) in the UIBackgroundModes key in your Info.plist, but we are still unable to locate any VoIP services. Apps that declare support for VoIP in the UIBackgroundModes key in your Info.plist file must have features that require VoIP. My app rejected for VOIP and the app is totally supported video call or call when app is terminated or in background how can. i solve that rejection issue

At WWDC 2023, the background asset feature was introduced, allowing essential resources to be downloaded before the game is first launched. How does this differ from including all necessary resources directly in the installation package? What are the advantages of this approach, and how does it enhance the user experience?

Dear Apple Developer Support, I have a question regarding the Background Assets feature for a game we are planning to release on the App Store. Specifically, I would like to understand the user experience during the initial installation process. If our game utilizes the Background Assets feature and we have essential assets specified in the BAExtension, will the end user need to wait for these essential assets to be fully downloaded before they can open the game after installing it from the App Store? Additionally, during this download process, will there be any indication of the essential assets' download status on the App Store or on the home screen icon of the game? Your guidance on how this process is managed and what the user can expect would be greatly appreciated. Thank you for your assistance.

Hello, I have applied background assets on my app. It does allow you to download resources in advance, increasing the speed of resource presentation. But I found that the download success rate was only 20% (Within an app with tens of millions of users). And most of the error codes are: BAErrorDomain Code=111 "The requested download could not be enqueued. Check the device‘s Low Power Mode or Background App Refresh settings" . Generally speaking, the proportion of low power mode should be around 20%. So why are there so many 111 error codes