Hello Apple Forums, We are developing an iOS application that connects to a custom BLE accessory and sends control commands to it. Our system architecture is as follows: A separate hardware device collects data and sends it to our backend server via Wi-Fi. The backend evaluates state changes and determines when the BLE accessory should update its display. The iOS app acts purely as a BLE command executor for this accessory. Our goal is to: Maintain a BLE connection with the accessory while the app is in the background. Receive state-change events from our backend server. Upon receiving such events, send a BLE command to the accessory to update its state. We understand that iOS does not allow arbitrary background execution. We would like to confirm whether there is any supported mechanism, entitlement, or program that allows: Long-running background execution for BLE control, or Server-originated events (other than APNs) to trigger background BLE actions. If this is not supported, we would appreciate confirmation that APNs (silent push) is the only supported way to trigger such background BLE actions, or guidance on any recommended alternative architectures. Thank you for your guidance.

I am developing a standard UAC 2.0 device and encountered an issue where the channel names do not update according to the iChannelNames field in the Class Specific AS Interface Descriptor when switching between different channel counts. For example: AS1 (6 channels) is configured with the following channel names: ADAT 1, ADAT 2, ADAT 3, ADAT 4, HP L, HP R AS2 (4 channels) is configured with: ADAT 1, ADAT 2, HP L, HP R However, when switching from AS1 (6 channels) to AS2 (4 channels), the channel names displayed in Audio MIDI Setup do not reflect the change as expected. The actual result is: ADAT 1, ADAT 2, ADAT 3, ADAT 4 The system simply hides the last two channels; the names of the remaining channels are not updated. Initial Topology My original topology was as follows: Later, I discovered that macOS uses the iChannelNames field from the Input Terminal to display channel names. Therefore, I modified the USB device descriptors and updated the topology to the following: To distinguish the channel names for different channel counts, each Input Terminal is assigned a unique iChannelNames value. This method worked perfectly on macOS 15. However, after updating to macOS 26, this topology no longer displays the correct channel names. Question On macOS 26, what is the correct method to ensure that the channel names update dynamically when switching between different audio channel configurations?

I am developing a standard UAC 2.0 device and encountered an issue where the channel names do not update according to the iChannelNames field in the Class Specific AS Interface Descriptor when switching between different channel counts. For example: AS1 (6 channels) is configured with the following channel names: ADAT 1, ADAT 2, ADAT 3, ADAT 4, HP L, HP R AS2 (4 channels) is configured with: ADAT 1, ADAT 2, HP L, HP R However, when switching from AS1 (6 channels) to AS2 (4 channels), the channel names displayed in Audio MIDI Setup do not reflect the change as expected. The actual result is: ADAT 1, ADAT 2, ADAT 3, ADAT 4 The system simply hides the last two channels; the names of the remaining channels are not updated. Initial Topology My original topology was as follows: Later, I discovered that macOS uses the iChannelNames field from the Input Terminal to display channel names. Therefore, I modified the USB device descriptors and updated the topology to the following: To distinguish the channel names for different channel counts, each Input Terminal is assigned a unique iChannelNames value. This method worked perfectly on macOS 15. However, after updating to macOS 26, this topology no longer displays the correct channel names. Question On macOS 26, what is the correct method to ensure that the channel names update dynamically when switching between different audio channel configurations?

Hello, I am an individual developer working on a macOS application using SwiftUI and RealityKit. I would like to understand the feasibility of face-related tracking on macOS when using an external USB camera, compared to iOS/iPadOS. Specifically: • Does macOS provide an ARKit Face Tracking–equivalent API (e.g., real-time facial expressions, gaze direction, depth)? • If not, is it common to rely on Vision / AVFoundation as alternatives for: • Facial expression coefficients • Gaze estimation • Depth approximation • In an environment without dedicated sensors such as TrueDepth, is it correct to assume that accurate depth data and high-fidelity blend shape extraction are realistically difficult? Any clarification on official limitations, recommended alternatives, or relevant documentation would be greatly appreciated. Thank you.

Hi all, I’m facing a device-specific issue in a live production iOS app distributed privately via the App Store . The app crashes immediately after login on one client’s iPhone, while the same account works fine on other devices. There’s no crash log generated in Analytics, and the app just pops to the home screen. Environment: App: Production app on App Store iOS version: 26.3 Devices: Only one device exhibits the crash; other iPhones work fine Login flow: App calls an API and writes the response to a local SQLite database immediately after login Distribution: App Store (Privately). The user is install via the redemption codes. Observations: All users on the problematic device crash immediately after login. The crash does not occur on any other devices, including the same iOS version. The client had already uninstalled and reinstalled the app via App Store cloud download, but the crash persisted. No crash log appears in Analytics or Xcode (process just terminates). Device restart had not been attempted before reinstall. App does not use Keychain tokens; local DB is only SQLite in the app sandbox. Hypotheses so far: Corrupted binary or cached app installation on that device SQLite database corruption or write failure Device-specific OS/environment issue (temp files, file locks, provisioning) iOS watchdog silently terminating the app during post-login DB write Language / region differences unlikely Questions: Is it possible for a device to retain a corrupted app binary or cached installation even after uninstall + cloud download reinstall from the App Store? Can uninstalling, restarting the device, and reinstalling guarantee a fresh binary and sandbox? Are there any known iOS behaviors where a local SQLite write could trigger an instant crash on one device only, without generating crash logs? Any other suggestions for diagnosing this device-specific post-login crash in a live production environment? Thanks in advance for any guidance — this issue is affecting a client’s live usage, and we’d like to understand the root cause and best way to resolve it safely.

Hello Apple Developer Technical Support Team, I’m working on an iOS banking/security SDK and we’re trying to match an Android feature that reads payment cards via NFC (EMV). On Android, this is implemented using an NFC scanning screen (e.g., “NfcScanActivity”) that can read EMV data from contactless credit/debit cards. Could you please clarify the current iOS capabilities and App Store policy around this? On iOS, is it currently possible for a third-party App Store app to read contactless credit/debit cards using Core NFC (i.e., accessing EMV application data/AIDs from payment cards)? If this is possible, what are the supported APIs/frameworks and any entitlement requirements (if applicable)? If this is not possible for App Store apps, could you recommend the closest acceptable alternatives for achieving a similar user outcome? For example: Using Apple Pay / PassKit flows for payment-related experiences Card scanning alternatives (camera-based OCR) for capturing card details (if allowed) Using an external certified card reader accessory (MFi) and required approach/entitlements Any other Apple-recommended approach for “card verification / identification” without reading EMV NFC data Our goal is not to bypass security restrictions, but to provide a compliant solution on iOS comparable to Android’s NFC-based card reading, or to adopt an Apple-approved alternative if direct EMV reading is not supported. If helpful, I can share a brief technical summary of the Android behavior and the exact data we need to obtain (e.g., whether it’s card presence verification vs. reading specific EMV tags). Thank you for your guidance. Best regards, Imran

After update to ipad OS 26.4 or latest 26.3., we’ve been experiencing issues with focusing. We have an app that scans 1x1 cm QR or DataMatrix codes from a distance of 10–20 cm, and users across different devices (ipad 9 and 10) are reporting problems. I didn’t find anything related to the camera in the version changelog, but users from various places are reporting problem with camera.

DJI's DNG files display abnormally in the Apple Photos app on iOS devices, with dark areas showing as very black, but the same files appear normal in Photoshop. I'm curious about what causes this issue.

I am creating a barcode reader using the AVfoundation framework for iOS and IPadOS. The read result goes into payloadstringvalue, but I want to check the control characters contained in the symbol, so I am using the raw data of the description, which is a property of NSObjectProtocol inherited by VNBarcodeObservation. However, I noticed that if the length set in the raw data exceeds 26, some of the raw data in the description is omitted. So my question is, is it possible to set it so that all the raw data in the description is written out without omitting any raw data? If so, could you please tell me how to set this up? Also, if you know of any other way to extract the raw barcode data, I would appreciate it if you could let me know. Thank you.

I am using NFC when the phone is near the NFC reader times below the error： 2024-07-15 15:43:03.608427+0800 TestNFC[16022:1038141] [xpc.exceptions] <NSXPCConnection: 0x282ba90e0> connection to service with pid 58 named com.apple.nfcd.service.corenfc: Exception caught during decoding of received selector didDetectExternalReaderWithNotification:, dropping incoming message. Exception: Exception while decoding argument 0 (#2 of invocation): Exception: decodeObjectForKey: class "NFFieldNotification" not loaded or does not exist my code: #import <CoreNFC/CoreNFC.h> @interface ViewController ()<NFCTagReaderSessionDelegate> @property (strong, nonatomic) NFCTagReaderSession *session; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. self.view.backgroundColor = [UIColor whiteColor]; if (@available(iOS 13.0, *)) { // 初始化 NFC 设置代理 NFCTagReaderSessionDelegate if (NFCNDEFReaderSession.readingAvailable) { self.session = [[NFCTagReaderSession alloc] initWithPollingOption:NFCPollingISO14443 delegate:self queue:nil]; // NFC 显示提示信息 self.session.alertMessage = @"准备扫描，请将卡片贴近手机"; // 开启 NFC [self.session beginSession]; } } else { } } #pragma mark - NFCNDEFReaderSessionDelegate //读取失败回调-读取成功后还是会回调这个方法 - (void)tagReaderSessionDidBecomeActive:(NFCTagReaderSession *)session API_AVAILABLE(ios(13.0)){ NSLog(@"tagReaderSessionDidBecomeActive"); } - (void)tagReaderSession:(NFCTagReaderSession *)session didInvalidateWithError:(NSError *)error API_AVAILABLE(ios(13.0)){ NSLog(@"readerSession:didInvalidateWithError: (%@)", [error localizedDescription]); } - (void)tagReaderSession:(NFCTagReaderSession *)session didDetectTags:(NSArray<__kindof id<NFCTag>> *)tags API_AVAILABLE(ios(13.0)){ }

I have a 4-input, 4-output hardware device and an 8-input, 8-output virtual device, which I combine into an aggregate device. I am using the SimplyCoreAudio library to get the channel count. The code is as follows: aggregationDevice!.channels(scope: .input) =>> 12 aggregationDevice!.channels(scope: .output) =>> 12 When the program's MicrophoneMode is set to standard, the channel count is correct. However, when I set the MicrophoneMode to voiceIsolation, the channel count is incorrect: aggregationDevice!.channels(scope: .input) =>> 4 aggregationDevice!.channels(scope: .output) =>> 12 Below is the code for creating the aggregate device： func createAggregateDevice(mainDevice: AudioDevice, secondDevice: AudioDevice?, named name: String, uid: String) -> AudioDevice? { guard let mainDeviceUID = mainDevice.uid else { return nil } var deviceList: [[String: Any]] = [ [ kAudioSubDeviceUIDKey: mainDeviceUID, kAudioSubDeviceDriftCompensationKey:1 ] ] // make sure same device isn't added twice if let secondDeviceUID = secondDevice?.uid, secondDeviceUID != mainDeviceUID { deviceList.append([ kAudioSubDeviceUIDKey: secondDeviceUID, kAudioSubDeviceDriftCompensationKey:1, kAudioSubDeviceInputChannelsKey:8 ]) } let desc: [String: Any] = [ kAudioAggregateDeviceNameKey: name, kAudioAggregateDeviceUIDKey: uid, kAudioAggregateDeviceSubDeviceListKey: deviceList, kAudioAggregateDeviceMainSubDeviceKey: mainDeviceUID, kAudioAggregateDeviceIsPrivateKey:false, ] var deviceID: AudioDeviceID = 0 let error = AudioHardwareCreateAggregateDevice(desc as CFDictionary, &deviceID) guard error == noErr else { return nil } return AudioDevice.lookup(by: deviceID) } I hope someone can tell me the reason Thank you！

Our company is developing an MFi headset with a button that we would like to use for initiating PTT. We can detect the button press and initiate PTT successfully, even when the app is not in the foreground, using the ExternalAccessory framework. But I wonder if this is a coincidence, or a scenario that should reliably work with Push to Talk?

While compiling nRF5340 target of Dockkit ADK 1.0 following the guide of README.md, I selected the latest Nordic SDK, because there is no specified SDK version in the README.md. But it seems that ADK and SDK are not compatible with each others. For example, it calls nrfx_gpiote_channel_alloc() with one argument in PAL\NCS\HAPPlatformExperience.c. But the difinition of this function needs two arguments. Also I found that in some older version of Nordic SDK, this function needs only one argument. So could you please make sure which version of Nordic SDK should developer use?

After hardware and mobile phone hid mode pairing, the first connection is successful, after a while disconnect and reconnect,APP monitoring Bluetooth error NSLocalizedDescription = "Peer removed pairing information"; Failed to connect Hardware engineers detect the pairing information and find that the local pairing information of the iPhone has changed, which is a non-mandatory phenomenon

Hi, i'm unable to select a icc profile on the new macbook Pro M4. How can i calibrate the internal screen by adding an icc profil made with my X-Rite color calibrator. icc files cannot be selected (grey) from the import menu of the monitor preferences.

We are currently managing our iPhones and iPads using Microsoft Intune and I wanted to get your feedback on other Enterprise management software that gives the admin the ability to manage more granular functions.

I'm device manufacturer and in future planning to get my device matter certified. If I want my device data for analytics purpose into my cloud than what is the best way possible. My research says that the most latest approach suggested by apple is, developing a custom mobile app using device homekit sdk and subscribe to device state and send it to my cloud. If I go that route, will it work even though the device was onboarded via homekit app and homekit hub device is also there. I want to make sure that both path will be active, device to hub to home app and device to custom app to my cloud, and both on matter ecosystem. The homekit sdk and matter support mentioned here https://developer.apple.com/apple-home/matter, are these two same thing?

I have an accessory with MFi authenticaiton passed(got 0xAA05) and identification accepted (got 0x1D02). But when I try to open the target stream by using iAP2 EA session framework, I always enounter the same error looking like: XPC connection error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service named com.apple.accessories.externalaccessory-server was invalidated from this process." UserInfo={NSDebugDescription=The connection to service named com.apple.accessories.externalaccessory-server was invalidated from this process.} anybody can tell me what it related with? And what can I do to go through it quickly? Thank you much in advance.

Hi I am implement my app with Core NFC , I found the module have their own UI , can I implement without the UI? we want the NFC scanning in background , not blocking the UI.

We are developing a matter device. How can we display our own APP under the Home device information?