Use HealthKit to enable your iOS and watchOS apps to work with the Apple Health app.

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Apple Watch Data to Server
I was wondering which is the preferred way to send a lot of data from sensors of the apple watch to server. It is preferred to send small chucks to iphone and then to server or directly send bulk data to server from watch. How does it affect battery and resources from watch ? Are there any triggers that I can use to ensure best data stream. I need to send at least once a day. Can I do it in background or do I need the user to have my app in the foreground ? Thank you in advance
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227
Jun ’25
Workout Buddy not available
Has anyone seen the workout buddy options on watch OS yet? I am not able to get it on my watch. My setup is an iPhone 16 and Watch Ultra 1 with the 26 OS I am currently using beta 3. English US language on both and US as region. I am located in Germany though. I restarted both devices multiple times without any changes. Hopefully someone can help.
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137
Jul ’25
HKLiveWorkoutBuilder get wrong calorie data for iOS 26
In iOS 26, HKLiveWorkoutBuilder is supported, which we can use like HKWorkoutSession in watchOS - this is very exciting. However, it currently seems to have a bug in calculating calories. I tested it in my app, and for nearly 6 minutes with an average heart rate of 134, it only calculated 8 calories consumed (80 calories per hour), including basal consumption, which is obviously incorrect. (I used Powerboats Pro 2 connected to my phone, which includes heart rate data, and HKLiveWorkoutBuilder correctly collected the heart rate, which is great.) I think my code is correct. func workoutBuilder(_ workoutBuilder: HKLiveWorkoutBuilder, didCollectDataOf collectedTypes: Set<HKSampleType>) { for type in collectedTypes { guard let quantityType = type as? HKQuantityType else { return // Nothing to do. } let statistics = workoutBuilder.statistics(for: quantityType) if let statistics = statistics { switch statistics.quantityType { case HKQuantityType.quantityType(forIdentifier: .heartRate): /// - Tag: SetLabel let heartRateUnit = HKUnit.count().unitDivided(by: HKUnit.minute()) let value = statistics.mostRecentQuantity()?.doubleValue(for: heartRateUnit) let roundedValue = Double( round( 1 * value! ) / 1 ) if let avg = statistics.averageQuantity()?.doubleValue(for: heartRateUnit) { self.avgHeartRate = avg } self.delegate?.didUpdateHeartBeat(self, heartBeat: Int(roundedValue)) case HKQuantityType.quantityType(forIdentifier: .activeEnergyBurned): let energyUnit = HKUnit.kilocalorie() let value = statistics.sumQuantity()?.doubleValue(for: energyUnit) self.totalActiveEnergyBurned = Double(value!) print("didUpdate totalActiveEnergyBurned: \(self.totalActiveEnergyBurned)") self.delegate?.didUpdateEnergyBurned(self, totalEnergy: self.totalActiveEnergyBurned + self.totalBasalEneryBurned) return case HKQuantityType.quantityType(forIdentifier: .basalEnergyBurned): let energyUnit = HKUnit.kilocalorie() let value = statistics.sumQuantity()?.doubleValue(for: energyUnit) self.totalBasalEneryBurned = Double(value!) print("didUpdate totalBasalEneryBurned: \(self.totalBasalEneryBurned)") self.delegate?.didUpdateEnergyBurned(self, totalEnergy: self.totalActiveEnergyBurned + self.totalBasalEneryBurned) return default: print("unhandled quantityType=\(statistics.quantityType) when processing statistics") return } } I think I've found the source of the problem: let workoutConfiguration = HKWorkoutConfiguration() workoutConfiguration.activityType = .traditionalStrengthTraining //walking, running is ok workoutConfiguration.locationType = .outdoor When I set the activityType to walking or running, the calorie results are correct, showing several hundred calories per hour. However, when activityType is set to traditionalStrengthTraining or jumprope, the calculations are incorrect. PS: I'm currently using Xcode 26 beta3 and iOS 26 beta3. Hope this issue can be resolved. Thanks.
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159
Jul ’25
Best Practices for Continuous Background Biometric Monitoring on Apple Watch
Hello, everyone! I'm seeking some guidance on the App Store review process and technical best practices for a watchOS app. My goal is to create an app that uses HealthKit to continuously monitor a user's heart rate in the background for sessions lasting between 30 minutes and 3 hours. This app would not be a fitness or workout tracker. My primary question is about the best way to achieve this reliably while staying within the App Store Review Guidelines. Is it advisable to use the WorkoutKit framework to start a custom, non-fitness "session" for the purpose of continuous background monitoring? Are there any other recommended APIs or frameworks for this kind of background data collection on watchOS that I should be aware of? What are the key review considerations I should be mindful of, particularly regarding Guideline 4.1 (Design) and the intended use of APIs? My app's core functionality would require this kind of data for a beneficial purpose. I want to ensure my approach is technically sound and has the best chance of a successful review. Any insights or advice from developers who have experience with similar use cases would be incredibly helpful! Thank you!
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429
Aug ’25
Possible to bring back "Time in Bed" iOS feature?
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
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612
Oct ’25
Rejected using Healthkit
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!
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321
Oct ’25
Feature Request: Expand HealthKit Body Composition Data Types to Support Smart Body Scanning Scales
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.
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167
Oct ’25
Unable to receive HealthKit updates when app is force-quit — need clarification on background delivery limits
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.
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165
Oct ’25
Medication data insert from third party app
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]) } } }
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987
Oct ’25
HealthKit in React Native + Expo Dev Client: no authorization prompt (and no data)
Hi everyone, I’m building a health app with React Native using Expo Dev Client on a real iPhone. I need to read Apple Health (HealthKit) data, but the authorization sheet never appears—so the app never gets permissions and all queries return nothing. What I’ve already done Enabled HealthKit capability for the iOS target. Added NSHealthShareUsageDescription and NSHealthUpdateUsageDescription to Info.plist. Using a custom dev build (not Expo Go). Tested fresh installs (deleted the app), rebooted device, and checked Settings → Privacy & Security → Health/Motion & Fitness. Tried both packages: react-native-health and @kingstinct/react-native-healthkit. Same behavior: no permission dialog at first use. Ask Is there a known reason why the HealthKit permission sheet would not show on modern iOS when called from a React Native bridge (with Expo Dev Client)? Are there any extra entitlements, signing, or config-plugin steps required beyond HealthKit capability + Info.plist? If you’re successfully fetching Apple Health data from React Native on recent iOS, could you share the exact steps that made the permission sheet appear and data flow (Expo config/plugin used, Xcode capability setup, profile/team settings, build type, bundle ID nuances, any Health app reset steps, etc.)? This would help me and others hitting the same “authorized call but no prompt/no data” issue. Thank you!
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279
Oct ’25
AirPods Pro 3 HRV Data Access Through HealthKit?
Hey everyone I'm working on a health app that's heavily focused on HRV tracking and analysis, and I'm trying to figure out what's actually possible with AirPods Pro 3 from a developer standpoint. The hardware clearly has a much better heart rate sensor than the previous generation, but I'm hitting some walls when it comes to actually accessing the data I need. So here's the situation I'm dealing with: When I query HealthKit for HRV samples, I'm not seeing anything coming from AirPods Pro 3. The device is obviously capable of tracking heart rate continuously during workouts and listening sessions, and from what I've read about the hardware, it should theoretically be able to capture the inter-beat intervals needed for HRV calculation. But either that data isn't being processed on-device, or it's just not being made available through the standard HealthKit data types that third-party apps can access. What I'm really after is either direct HRV metrics (like SDNN, which Apple Watch already provides through HKQuantityTypeIdentifierHeartRateVariabilitySDNN) or even better, access to the raw R-R interval data. With R-R intervals, I could calculate RMSSD, pNN50, and other time-domain and frequency-domain HRV metrics that are super valuable for tracking recovery, autonomic nervous system balance, and stress levels. This would be especially useful since a lot of users wear AirPods during activities when they're not wearing their Apple Watch. Has anyone managed to find a way to pull this data from AirPods Pro 3? Are there any private frameworks or entitlements I should be looking into? Or is this just fundamentally not exposed to developers at the OS level right now? I've gone through the HealthKit documentation pretty thoroughly and haven't found anything that specifically addresses this, but I'm wondering if I'm missing something or if there are any known workarounds. I'm also curious if anyone has heard anything from Apple about future plans to expose this data. It seems like a missed opportunity given how capable the hardware is and how much value developers could provide with access to this physiological data. Would love to hear if anyone else is working on similar features or has insights into the technical limitations here.
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725
Oct ’25
Enabling Cycling Power Read from Garmin Connect To Health
I am working on a cycling fitness app and I want to read the cycling power recorded using my Garmin edge from the Garmin Connect App. Currently the data is not transferred to the Health/Fitness Apps. Ideally it would be good to be able to query the power samples similar to the heart rate samples, but even the average power would suffice, as I could then calculate the Kilojoules.
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178
Nov ’25
Is it possible to distinguish real vs manually added running data in HealthKit?
I am developing an iOS application that utilizes running workout data from the iOS Health app / Fitness app via HealthKit, with explicit user permission. Before finalizing the app design, I would like to clarify several technical aspects related to data reliability, manual entry, record modification, and GPS route availability in HealthKit. My questions are as follows: 1. Identifying manually added (non-physical) running workouts When a running workout is created in the Health app without actual physical movement (for example, a workout manually added by the user), is there any metadata, flag, or key in HealthKit that allows developers to distinguish these records from workouts generated through actual motion tracking (iPhone or Apple Watch)? 2. Editing existing running workout records Is it possible for users, or for third-party apps with HealthKit write permission, to edit an existing running workout (e.g., distance, duration, calories) after it has been saved? • If edits are allowed, are the original values preserved in any way, or are they fully overwritten? 3. Detecting modified workout records If a running workout (whether originally auto-recorded or manually created) has been edited after creation, is there any identifier, metadata field, source revision, or versioning mechanism in HealthKit that allows developers to detect that the workout has been modified? 4. Access to GPS route / running path data For outdoor running workouts recorded with location services enabled: • Does HealthKit provide access to GPS route data (running paths / location traces) associated with a workout? • Is this route data accessible to third-party apps with user permission? • Is route data available only for workouts recorded on Apple Watch, or also for iPhone-only recordings? • Is there a way to determine programmatically whether a running workout includes valid GPS route data? The overall goal is to understand whether, when building an app that relies on HealthKit running data, it is technically possible to differentiate motion-based workouts from manually added or edited records, and to assess the availability of route information for outdoor runs. Any clarification or references to official documentation would be greatly appreciated. Thank you
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163
Dec ’25
Guideline 2.5.1 - Performance - Software Requirements
Hi all, I'm developing fitness app and I use healthkit to track user's "STEPS" count and "Heart Rate" 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. How I tried to Resolve the Issue I have modified my app: adding user permission prompt, adding healthkit notification, adding healthkit indicator in the UI **1. Added a "Permission Primer" Screen (Pre-Alert) ** When a user taps "Connect Apple Health," they are now shown a dedicated explanation screen before the system permission prompt appears. This screen clearly states: "[App] integrates with HealthKit to read your Heart Rate and Steps... to calculate physical exertion." (Please see the "Connect" flow in the Session Detail view). **2. Added Explicit Source Attribution ** I have added a permanent text label reading "Health data sourced from Apple Health" directly below the heart rate and steps statistics on the Session Detail dashboard. This ensures that users always identify the source of the displayed metrics. 3. Deployment Target Correction I identified a configuration error where the Deployment Target was set to a future OS version. I have corrected this to the currently shipping iOS 18 to ensure full compliance with software requirements. 4. App Description Update I have updated the App Store description to explicitly mention the HealthKit integration and its specific purpose (tracking match intensity). However doing the above, I still continue to receive the same review 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!
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2w
iBeacon Monitoring in Flutter App: Background Wake-Up from Killed State, Time Limits for BLE, and Handling Multiple Regions/Identifiers
Hello Apple Developer Community, I'm developing a cross-platform app using Flutter and the flutter_beacon library to handle iBeacon detection on iOS. My goal is to wake up the app in the background when it's in a killed/terminated state upon entering/exiting beacon regions, allowing for BLE communication (e.g., ranging or connecting to beacons). I've configured the necessary Info.plist keys for always location access and background location modes, and it works partially for single regions, but I have some specific questions/issues regarding reliability and limitations: Background Execution Time After Wake-Up: When the app is woken in the background by a region monitoring event (enter/exit) from a killed state, approximately how much time (in seconds) does iOS allocate for the app to run before suspending it again? Is this sufficient for performing BLE operations like ranging beacons or establishing a short connection, or are there stricter limits in terminated wake-ups compared to standard background modes? Monitoring Multiple iBeacons with Unique Identifiers: I need to monitor multiple iBeacon devices, each with potentially different UUIDs, majors, and minors. Can I add and monitor up to 20 regions simultaneously, each with a unique string identifier? If multiple beacons (from different regions) enter their respective ranges at around the same time, will the app receive separate callbacks for each region/identifier, or is there coalescing/prioritization that might cause only the last-added identifier to trigger notifications/events? Reliability in Killed State: In a fully killed state (e.g., force-quit via app switcher), does iOS reliably relaunch the app in the background for region monitoring events? Are there any known caveats, such as requiring specific hardware (e.g., iPhone models with certain Bluetooth chips) or iOS versions (targeting iOS 14+), and how does this interact with Flutter's background execution handling via the flutter_beacon library?
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99
5d
[After iPhone migration] Health app permissions for connected app are not shown
After upgrading to a new iPhone and restoring from an iCloud backup using the same Apple ID, I noticed an issue with Health app permissions. ■ What is happening On my previous iPhone, an app had permission to read step count data. After restoring to the new iPhone, the app still appears in the Health app under Sources. However, when I tap the app, the usual data type permission toggles (such as Steps) are not displayed at all. As a result, the app is unable to read step count data. ■ Additional details The app itself seems to be recognized as a Health data source. However, the data type permission screen is empty. No ON/OFF switches are shown. The backup was created on iOS 18, and the restore was performed on iOS 26. I have not yet confirmed whether this also happens with other iOS version combinations. ■ Questions Is it expected behavior that Health app permissions (per data type) are not restored via iCloud backup? Has anyone experienced a similar situation where the app appears under Sources but the permission options are missing? If so, how did you resolve it? Any information from users who have experienced the same issue would be greatly appreciated.
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36
1d
[WatchOS] Error while trying to insertRouteData into HKWorkoutRouteBuilder
I've ran into an error with the insertRouteData function of the HKWorkoutRouteBuilder that I can't seem to find any information on. The error is "Unable to find location series 1A193D3B-AFF5-41D8-A967-B1BE08D9F543 during data insert.". It seems to only happen when trying to insert very long routes, in the most recent case it was a 5 hour bike ride with 5900 samples. I save all the route data in a sqlite table as backup and after checking out the data there isn't any red flags as to why it would not insert correctly. Has anyone seen this before and could offer some insight or point me in the right direction to find the source of the error?
2
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1.2k
Jan ’26
HKAnchoredObjectQuery updateHandler stops working with error
Hi! I am using the HKAnchoredObjectQuery to first get a snapshot of the initial results, and then trigger an updateHandler. I need to handle the initial results and the updates separately, which is why I implemented two completions. When I test the code, it works for a while. New and deleted samples trigger the updateHandler. However, after a while there appears an error: [connection] nw_read_request_report [C2] Receive failed with error "Software caused connection abort" Followingly, the updateHandler will stop getting triggered when I add updates in Apple health. Anyone have experience with this? func getMostRecentSample(for sampleType: HKSampleType, anchorKey: String, completion: @escaping (HKQuantitySample?, Error?) -> Swift.Void, updateHandler: @escaping (HKQuantitySample, Error?) -> Swift.Void) {     // If it is the first initialization, anchor is passed as nil     var anchor: HKQueryAnchor? = nil // Check for previous saved anchor in userdefaults     if UserDefaults.standard.object(forKey: anchorKey) != nil {       let data = UserDefaults.standard.object(forKey: anchorKey) as! Data       do {         guard let newAnchor = try NSKeyedUnarchiver.unarchivedObject(ofClass: HKQueryAnchor.self, from: data) else {           print("Could not parse anchor to HKQueryAnchor type")           return         }         anchor = newAnchor       } catch {         print("Error retreiving anchor from UserDefaults")       }     }     let query = HKAnchoredObjectQuery(type: sampleType,                      predicate: nil,                      anchor: anchor,                      limit: HKObjectQueryNoLimit                       ) { (query, samplesOrNil, _, newAnchor, errorOrNil) in       guard let samples = samplesOrNil as? [HKQuantitySample] else {         fatalError("*** An error occurred during the initial query: \(errorOrNil!.localizedDescription) ***")       }       if let anchor = newAnchor {         do {           let data = try NSKeyedArchiver.archivedData(withRootObject: anchor as Any, requiringSecureCoding: false)           UserDefaults.standard.set(data, forKey: anchorKey)         } catch {           print("Error retreiving anchor from UserDefaults")         }       }       completion(samples.last, nil)     }           // Setting up long-running query     query.updateHandler = { (query, samplesOrNil, _, newAnchor, errorOrNil) in       guard let samples = samplesOrNil as? [HKQuantitySample] else {         fatalError("*** An error occurred during an update: \(errorOrNil!.localizedDescription) ***")       }       if let anchor = newAnchor {         do {           let data = try NSKeyedArchiver.archivedData(withRootObject: anchor as Any, requiringSecureCoding: false)           UserDefaults.standard.set(data, forKey: anchorKey)         } catch {           print("Error retreiving anchor from UserDefaults")         }       }       if let sample = samples.last {         updateHandler(sample, nil)       }     }     self.healthStore.execute(query)   }
2
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1.2k
Mar ’25
HKWorkoutSession.sendToRemoteWorkoutSession doesn't report success or failure
We are seeing an issue where sending data using the asynchronous method HKWorkoutSession.sendToRemoteWorkoutSession(data: Data) will never return in some cases (no success nor failure). This issue is happening for roughly 5% of Workouts started and will stay broken for the whole workout. The other 95% of the workouts, the connection works flawlessly. This happens on both watchOS 10 and 11, and with phones running iOS 17 or 18. The issue is quite random and not reproducible. Our app has thousands of workouts a day that use the workout session workout data send, with constant messages being send every few seconds. In some of those 5% cases the "sendToRemoteWorkoutSession" will throw way later, like 30+ minutes later, if the watch app is awake long enough to capture a log of a failure. Our code uses the same flow as in the sample project: https://developer.apple.com/documentation/healthkit/workouts_and_activity_rings/building_a_multidevice_workout_app Here is some sample code, which is pretty simple. Setup code: let workoutSession = try HKWorkoutSession(healthStore: healthStore, configuration: configuration) workoutSession.delegate = self activeWorkoutSession?.startMirroringToCompanionDevice { success, error in print("Mirroring started on companion device: \(success), error: \(error)") } workoutSession?.prepare() then later we send data using the workout session: do { print("Will send data") try await workoutSession.sendToRemoteWorkoutSession(data: data) print("Successfully sent data") // This nor the error may be called after waiting extensive amounts of time } catch { print("Failed to send data, error: \(error)") // This nor the success may be called after waiting extensive amounts of time } So far, the only fix is to restart the phone and watch at the same time, which is not a great user experience. Is anyone else seeing this issue? or know how to fix this issue?
2
0
828
Dec ’25