I'm trying to make a watchOS app that uses sleep data to wake users up when they enter lighter sleep stages. Apple has HealthKit, which exposes HKCategoryValueSleepAnalysis to view each stage throughout sleep, but unfortunately, this data is only written after the user wakes up. I did some research and found that the Apple Watch’s sleep classifier is part of Apple’s private system process, and apps can’t access that model directly or as it’s running. So, there’s no way to “record” my own data stream and match it with Apple’s classification during the night. Has anyone found a way to approximate or access live sleep-stage data in another way? I’m thinking of combining CoreMotion (for movement) and heart rate data from a HKWorkoutSession to infer stages myself, but I’m wondering if there’s any Apple-approved or more accurate approach for this. In other words, is there any way to use an Apple Watch to detect sleep stages accurately while the user is still asleep for the purpose of timing an optimal wake-up? Thanks

I have a watchOS app with a connected iOS app using Swift and SwiftUI. The watchOS app should read heart rate date in the background using HKOberserQuery and enableBackgroundDelivery(), send the data to the iPhone app via WCSession. The iPhone app then sends the data to a Firebase project. The issue I am facing now it that the app with the HKObserverQuery works fine when the app is in the foreground, but when the app runs in the background, the observer query gets triggered for the first time (after one hour), but then always get terminated from the watchdog timeout with the following error message: CSLHandleBackgroundHealthKitQueryAction scene-create watchdog transgression: app<app.nanacare.nanacare.nanaCareHealthSync.watchkitapp((null))>:14451 exhausted real (wall clock) time allowance of 15.00 seconds I am using Xcode 16.3 on MacOS 15.4 The App is running on iOS 18.4 and watchOS 11.4 What is the reason for this this issue? I only do a simple SampleQuery to fetch the latest heart rate data inside the HKObserverQuery and then call the completionHandler. The query itself takes less than one second. Or is there a better approach to read continuously heart rate data from healthKit in the background on watchOS? I don't have an active workout session, and I don't need all heart rate data. Once every 15 minutes or so would be enough.

I'd like to investigate creating a safety feature for Type 1 Diabetics driving a car. Allowing HealthKit glucose data (read from a Dexcom G7 or similar) to be displayed as part of the CarPlay UI background or show an icon/button with the number visible. I'd also like to include a warning system for glucose low's that alerts the driver audibly. Has anyone looked into that before?

Hi, I have a workout app in the App Store which mirrors workout data between the phone and watch. Since iOS 26.x I've been having issues and received reports of the mirroring no longer working. Users in iOS 18 have no problems with this functionality. Bug description: A workout session is started from the phone app and starts mirroring to the watch companion device. The watch starts the workout session and then the mirroring session is disconnected / lost. Sending data to the companion device fails and ending the session on the phone doesn't end the session on the watch...essentially they become completely disconnected. Please note I am testing this on physical devices...not simulators. As a sanity check I've also tried the "Building a multidevice workout app" sample code and it has the same problem. To re-create on the sample app, I start a workout from the phone, the watch workout starts and then the mirroring session seems to disconnect and is unable to send data. This is the log from the "Building a multidevice workout app" sample code. Successfully started workout Type: Notice | Timestamp: 2025-10-17 06:57:07.341401+02:00 | Process: MirroringWorkoutsSample Watch App | Library: MirroringWorkoutsSample Watch App.debug.dylib | Subsystem: com.example.apple-samplecode.MirroringWorkoutsSampleABC123.watchkitapp | Category: MirroringWorkoutsSampleForWatch | TID: 0x1b2ca7 -[SPRemoteInterface _appRecoverAnyExtendedRuntimeSession:]_block_invoke:4350: Got no sessions back from -[CSLSSessionService existingRunningSessions:] or -[CSLSSessionService existingScheduledSessions:] after receiving a PUICInitializeSessionServiceAction Type: Error | Timestamp: 2025-10-17 06:57:07.641571+02:00 | Process: MirroringWorkoutsSample Watch App | Library: WatchKit | Subsystem: com.apple.watchkit | Category: default | TID: 0x1b2ca7 Session state changed from 1 to 2 Type: Notice | Timestamp: 2025-10-17 06:57:07.647883+02:00 | Process: MirroringWorkoutsSample Watch App | Library: MirroringWorkoutsSample Watch App.debug.dylib | Subsystem: com.example.apple-samplecode.MirroringWorkoutsSampleABC123.watchkitapp | Category: MirroringWorkoutsSampleForWatch | TID: 0x1b2e87 Failed to send data: Error Domain=com.apple.healthkit Code=100 "Failed to send data to remote session." UserInfo={NSLocalizedDescription=Failed to send data to remote session.} Type: Notice | Timestamp: 2025-10-17 06:57:07.669922+02:00 | Process: MirroringWorkoutsSample Watch App | Library: MirroringWorkoutsSample Watch App.debug.dylib | Subsystem: com.example.apple-samplecode.MirroringWorkoutsSampleABC123.watchkitapp | Category: MirroringWorkoutsSampleForWatch | TID: 0x1b2ca7 Would appreciate any help with this problem as it's affecting customers. Thank you

Hello, I’m building a health-related app for both watchOS and iOS, which needs to monitor certain health data (e.g., heart rate, active energy). Before updating to watchOS 26, the queries worked reliably without any issues. However, after adapting to watchOS 26, some users have reported that health data updates stop being delivered. What I’ve observed: HKObserverQuery with enableBackgroundDelivery is set up normally. On WatchOS 26, the query sometimes stops delivering updates entirely after a certain point, and once an update is missed, it may stop delivering further updates completely. Restarting the Apple Watch temporarily restores delivery, but the problem reoccurs after some time. This makes background health data monitoring unreliable for my app. Here’s a simplified version of the code we are using: guard let heartType = HKObjectType.quantityType(forIdentifier: .heartRate) else { return } let query = HKObserverQuery(sampleType: heartType, predicate: nil) { query, completionHandler, error in if let error = error { logEvent("Observer error: \(error.localizedDescription)") return } logEvent("Heart rate changed") MyNotificationManager.shared.sendNotification() // Send a local notification completionHandler() } healthStore.execute(query) healthStore.enableBackgroundDelivery(for: heartType, frequency: .hourly) { success, error in if success { logEvent("Background heart rate delivery enabled") } else { logEvent("Failed to enable background heart rate delivery: \(error?.localizedDescription ?? "Unknown error")") } } Could you please clarify: Is this a known issue with HKObserverQuery and enableBackgroundDelivery on watchOS 26? Are there any recommended workarounds or best practices to ensure continuous background delivery of health data? Thank you in advance for your help.

We are using HealthKit in our app to synchronize step count data. The data is correctly synced with the Health app, but the step count does not appear in the Fitness app (although workout data does). Is there anything developers need to do to synchronize step count data with the Fitness app as well?

I want to insert the medication data which is available from ios 26 from my app to apple health kit. I have tried to get the permission to read and write data but app got crashed while I tried to request that permission. Does apple allow to insert the medication data to apple health kit likewise we are able to add other health and fitness data or not? let healthStore = HKHealthStore() @available(iOS 26.0, *) @objc func requestAuthorization(_ resolve: @escaping RCTPromiseResolveBlock, rejecter reject: @escaping RCTPromiseRejectBlock) { guard HKHealthStore.isHealthDataAvailable() else { print("not available ") return } let doseType = HKObjectType.medicationDoseEventType() let medType = HKObjectType.userAnnotatedMedicationType() healthStore.requestAuthorization(toShare: [doseType], read: [doseType]) { success, error in if let err = error { reject("auth_error", err.localizedDescription, err); return } self.healthStore.requestPerObjectReadAuthorization(for: medType, predicate: nil) { s, e in if let err2 = e { reject("per_obj_auth", err2.localizedDescription, err2); return } resolve(["ok": success && s]) } } }

I'm reporting a critical Health data synchronization failure that began immediately after updating from watchOS 18 to watchOS 26.0.2 (stable release) and persists in watchOS 26.1 beta 2. Bug Description: Complete failure of Health data sync from Apple Watch to iPhone Health app. All health metrics are being captured and stored locally on the watch but fail to sync to the paired iPhone. Affected Data Types: Activity rings (Move, Exercise, Stand) Heart rate measurements Sleep tracking data Workout data All other HealthKit data points Environment: Device: Apple Watch Series 7 Initial failure: watchOS 26.0.2 (23R362) - stable release Current: watchOS 26.1 beta 2 (23S5052c) Paired iPhone: iPhone 17 Pro Max, iOS 26.1 beta 2 (23B5052c) Bluetooth and Wi-Fi connectivity: Normal Watch pairing status: Connected and functional for all other features Reproduction: Updated Apple Watch Series 7 from watchOS 18 to watchOS 26.0.2 on September 30, 2025 Health data sync ceased completely starting October 1, 2025 Issue persists after updating to watchOS 26.1 beta 2 and iOS 26.1 beta 2 Data remains stored locally on watch and is viewable in watch apps Apple Watch appears as connected data source in Health app but no data transfers Troubleshooting Performed: Multiple device restarts (both iPhone and Apple Watch) Bluetooth/Wi-Fi toggling and reconnection Verified Privacy > Motion & Fitness > Fitness Tracking and Health enabled on both devices Confirmed data source priority settings in Health app Extended charging periods to allow background sync operations Verified no Low Power Mode restrictions Impact: Critical functionality loss for primary Apple Watch use case. Unable to track longitudinal health data, breaking continuity of health records dating back to watchOS 18. Feedback Submitted: FB20533870 filed via Feedback Assistant with sysdiagnose from both devices Questions for Engineering: Is this a known regression in watchOS 26.0.2 or later builds? Are there any watchOS 26.1 beta release notes addressing HealthKit sync issues that I should review? Should I capture additional diagnostic data (e.g., specific console logs, HealthKit database states)? Is unpairing/re-pairing expected to resolve this, or would that indicate a deeper architectural issue? Additional Context: Apple Watch appears in Settings > Bluetooth as connected Can successfully change watch faces from iPhone Notifications, Messages, and calls work normally No previous sync issues prior to watchOS 26.0.2 Senior Apple Support advisor escalation completed; awaiting engineering review This appears to be a regression introduced in watchOS 26.0.2. Any guidance on additional diagnostics or confirmation of a fix in upcoming builds would be appreciated.

I researched Apple HealthKit Background Delivery documentation but I couldn't find any information about does HK background delivery stay persistent after restarting the device? Do I need to enable background delivery for each health data type on a reboot? Can you enlighten me about this topic.

Hello, I’m developing a HealthKit-based fitness app in React Native that observes step count changes and uploads the latest totals to a remote server. I’m currently using HKObserverQuery with background delivery enabled (enableBackgroundDelivery(for:frequency:.immediate)), and the behavior works correctly while the app is running in the background or foreground. Whenever new step data is written to HealthKit, the app wakes up, reads the latest data, and sends it to my HTTPS endpoint using URLSession.shared.dataTask inside the observer callback. However, I’ve noticed the following issue: 1. If the user swipes up (force-quits) the app from the app switcher, the observer queries stop firing entirely. 2. In this state, even though HealthKit continues collecting step data from the device or Apple Watch, my app no longer receives those background deliveries until the user opens the app again. What I would like to achieve is: When the app is terminated (swiped up), and there are new step count updates in HealthKit, my app should still be able to receive those updates or be relaunched to handle them — similar to how some health companion apps continue syncing data and sending notifications even after being force-quit. So I have a few questions: Is this limitation expected — i.e., does iOS intentionally block HKObserverQuery background deliveries after a user force-quits the app? 2. Are there any special entitlements, background modes, or Apple-approved mechanisms that allow a health or medical app to continue receiving HealthKit changes even after a force-quit? 3. If not, what is the recommended architecture for apps that need to process HealthKit data continuously and send it to a backend server? For example, should such apps rely on server-side push notifications or CloudKit sync once the user reopens the app? My current goal is to ensure step count changes are uploaded reliably even if the app is killed, but I want to stay within the system’s supported behaviors and privacy constraints. Any clarification or guidance from Apple engineers or others who have implemented continuous HealthKit sync (like companion or medical apps) would be greatly appreciated. Thank you.

Hello, My watchOS app has been performing fine by requesting background app refresh and then requesting any new data from health kit in the background so that the widget can be updated. However, on watchos26 I have been unable to read data in the background, with any query returning zero results. That same data is clearly read just fine while in the foreground. Can anyone assist?

We are developing a health app that relies on HKObserverQuery and BackgroundDelivery to monitor Heart Rate data. On watchOS 10.6 and 11.6 , these data updates are typically delivered reliably every 8–12 minutes, occasionally exceeding 12 minutes, but generally not longer than 15 minutes. This frequency has been sufficient for the real-time data requirements of our app. However, after adapting our app to watchOS 26, we noticed that HKObserverQuery triggers much less frequently, with longer and very inconsistent intervals. This issue has had a major impact on our product: data collection for essential features is unreliable, resulting in a greatly diminished user experience on watchOS 26 and making the app essentially useless from the user’s perspective. Observed Behavior: HKObserverQuery and BackgroundDelivery are extremely unstable, with trigger intervals frequently exceeding 15 minutes, and sometimes even 20 minutes. When the user is sedentary, intervals become even longer; there are cases where no heart rate or active energy updates are delivered for 30 minutes, or even over 1 hour. Request for Support and Guidance: Have there been any changes to the HKObserverQuery background delivery mechanism on watchOS 26, specifically for Heart Rate and Active Energy data? If these changes are intentional system optimizations, could you provide guidance or recommended practices to ensure our app can reliably retrieve updates and maintain a smooth experience for users? Thank you for your support.

Summary: Expanding HealthKit to support the full spectrum of smart scale metrics will allow Apple Health to remain the central hub for health data, align with user expectations, and future-proof the framework as body composition analysis evolves. Description: With the growing adoption of smart body composition scales (e.g. segmental impedance scanners, multi-frequency analyzers, and body pods), users are generating a wide variety of clinically relevant metrics that currently cannot be stored natively in HealthKit. At present, HealthKit supports a core set of body composition values (Body Mass, BMI, Body Fat %, Lean Mass, Height, Waist Circumference). While useful, these do not capture the full picture modern devices provide, leading to fragmentation: • Users can see dozens of metrics in the device app, but only a handful flow into Health. • Developers must resort to metadata fields, which are inconsistent across apps and not accessible in Apple’s Health app UI. This gap undermines HealthKit’s role as a central, standardized health record. ⸻ Proposed Additions: Expand HealthKit HKQuantityTypeIdentifier to include additional body composition and derived measurements commonly reported by smart scales: Core Body Composition • Visceral fat percentage / rating • Skeletal muscle mass • Segmental muscle mass (arms, legs, trunk) • Segmental fat mass (arms, legs, trunk) • Bone mineral mass • Total body water % / hydration Derived Health Metrics • Muscle-to-fat ratio • Phase angle (bioelectrical impedance) • Metabolic age • Basal metabolic rate (BMR) ⸻ Rationale: • User benefit: Health app would show a more complete health profile, not just weight and fat %. • Developer benefit: Creates standardized identifiers, eliminating the need for proprietary storage in metadata. • Industry alignment: Many leading health devices already provide these metrics; users expect them to sync into Health. • Future-proofing: As body scanning scales proliferate, HealthKit can remain the trusted central repository rather than ceding ground to siloed vendor apps. ⸻ Suggested Implementation: • Introduce new HKQuantityTypeIdentifier values for each metric. • Permit segmental values to be represented as discrete samples with metadata for body region. • Ensure values can be written by apps/devices and surfaced in Health app UI, just like existing body composition data.

I have an iPhone 11 Pro Max running iOS 26. But since iOS 18, Apple decided to remove the "Time in Bed" feature[1][2]. Is it possible to develop an app that, effectively, "brings back" this feature? It doesn't have to be that accurate. Just a gauge is fine. As a starter I would like to track the time the phone was in Sleep mode (regardless whether the phone is being used). I have a minimal programming background but have not developed an iOS app before so any help would be appreciated. I found out about HealthKit[3] which lets me access (edit?) Health data, but I don't know where to go from there. [1] https://www.reddit.com/r/iOSBeta/comments/1em8bl6/ios_181_db1_time_in_bed_via_iphone_feature_removed [2] https://www.reddit.com/r/ios/comments/1fkjat4/apple_removed_the_iphoneonly_sleep_tracking [3] https://developer.apple.com/documentation/healthkit

Hello, In my application, I need to obtain precise workout segment data from HKWorkout in order to calculate per-kilometer metrics such as heart rate and pace. My current approach is: 1.Use HKWorkout to fetch the associated HKWorkoutEvents. 2.Take the end time of one event as the start time of the next event to derive per-kilometer segment ranges. The issue I’m facing: •If a user sets Apple Watch to notify every 5 kilometers, then at 5 km, 10 km, 15 km, etc., I see overlapping event times. •From the HKWorkoutEvents data alone, I cannot distinguish between events that represent “per-kilometer splits” and those that represent “5-kilometer notifications.” •As a result, my per-kilometer heart rate and pace calculations can be inaccurate. My question is: Is there a recommended way to reliably differentiate per-kilometer splits from custom distance notifications and ensure accurate segment data retrieval? For example, should I instead reconstruct segments using HKWorkoutRoute and distance samples, rather than relying on HKWorkoutEvents? STEPS TO REPRODUCE 1.On Apple Watch, start an Outdoor Run using the Workout app. 2.In workout notifications, set distance alerts to every 5 kilometers. 3.During the run, when reaching 5 km, 10 km, 15 km, etc., the watch triggers notifications. 4.Query the corresponding HKWorkout from HealthKit and inspect its HKWorkoutEvents. 5.Notice that some event start times are duplicated, and it is unclear which events represent “per-kilometer splits” and which represent “5-kilometer notifications.” Expected Result: Be able to differentiate between per-kilometer splits and custom distance alerts, so that heart rate and pace per kilometer can be calculated accurately. Actual Result: The HKWorkoutEvents data contains duplicated event times without a way to distinguish event types, leading to inaccurate per-kilometer statistics.

Hi all, I'm developing fitness app and I use healthkit to track user's "STEPS" count from their iphone devices. I have been receiving this rejection and can't seem to get past this: Guideline 2.5.1 - Performance - Software Requirements The app uses the HealthKit or CareKit APIs but does not clearly identify the HealthKit and CareKit functionality in the app's user interface. Apps using these APIs should be clearly indicated to provide transparency and valuable information to users. Next Steps To resolve this issue, it would appropriate to clearly identify the HealthKit and CareKit functionality in the app's user interface. Resources Learn more about software requirements in guideline 2.5.1. I have modified my app: adding user permission prompt, adding healthkit notification, adding healthkit indicator in the UI, adding healthkit information in the onboarding process. I keep getting the same message. When I asked the reviewer what else could be done to satisfy the requirement, I only get boiler plate message above. Anyone know what they really looking for? Any insights is appreciated. Thanks!

Are there any HealthKit related changes to be aware of in the new update that enables SPO2 / Blood Oxygen Saturation measurements on certain Apple Watch models within the US? I’m aware of processing happening on the phone…. But beyond that: Does this mean values are then saved to Apple Health? Do these models still take background SPO2 measurements in the same way as other models do? Are these values then visible in third party iOS apps as normal through HealthKit? Do these values sync back to the paired Apple Watch HealthKit store for third party apps to access on the Watch? For reference I have an iOS and WatchOS app that, amongst other features, provides the ability to see your SPO2 values in the Watch app, complications and in the iOS app.

Hi everyone, I’m a student developer currently building a watchOS app that uses HealthKit and HKWorkoutSession to estimate core body temperature from real-time heart rate data. The app runs well in the simulator, but testing on a physical Apple Watch has been extremely difficult. Each time I try to run the app from Xcode (Version 16.3), the build gets stuck on: “Copying shared cache symbols from MyWatchName (0% completed)” Sometimes it just stops stating connection failure. However, more often no errors are shown, but the sync never finishes. I’ve tried the following without success: Restarting the watch, iPhone, and Xcode Switching networks (Wi-Fi and hotspot) USB wired pairing Resetting developer settings and trust prompts Deleting derived data Rebuilding the project This is especially limiting for a real-time health tracking app where I need to monitor HKLiveWorkoutBuilder data while the screen sleeps — which can’t be tested effectively in the simulator.

Hello, I have enabled HealthKit background delivery for sleep analysis samples: private func setupSleepDataBackgroundDelivery() { if let sleepType = HKObjectType.categoryType(forIdentifier: HKCategoryTypeIdentifier.sleepAnalysis) { healthStore.enableBackgroundDelivery(for: sleepType, frequency: .immediate) { (success, error) in } } } In general, this function works. But I would love to know what the limitations / expected delivery delay for frequency: .immediate is. The documentation is only very vague about this and specifies that some sample types such as steps are only delivered once per hour. But how about sleep data? Is this expected to be delivered immediately once available on iPhone? Thanks a lot for your help!

New in iOS 26 and WatchOS 26 is a Sleep Score calculation for users based on Duration, Bedtime and Interruptions. Unfortunately I can't find any APIs for developers to tap into this metric. Yes, in theory it's all created off the same Sleep Analysis data already available with HealthKit but that makes it very hard to recreate in our apps. If the numbers don't match up exactly, users will understandably complain. Can anyone confirm that this is the case and I've not missed a Sleep Score API? I'll then file feedback. Hopefully this doesn't go the way of Heart Rate Zones where the Apple Watch iPhone app has generated them for years and provided no way for third party apps to access these values (yes many feedbacks provided previously).