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

All subtopics
Posts under Health and Fitness topic

Post

Replies

Boosts

Views

Activity

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.
1
0
91
Nov ’25
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
0
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
607
1w
Deprecated: HKCategoryValueMenstrualFlow
We currently use the HKCategoryValueMenstrualFlow enum to determine the type of menstrual flow: light, medium, etc. a user is having. We also use this enum in determining if it's an actual period day. The Problem I see HKCategoryValueMenstrualFlow was recently deprecated but has not been replaced by another data type. Are there plans to replace/update it with another data type? When or at what point in the future will this deprecation cause a problem in my code?
2
1
968
Dec ’24
Read Workout Effort Scores
Is there documentation on how to read workout effort scores from a HealthKit workout? I'm interested in reading workoutEffortScore and estimatedWorkoutEffortScore. I have not been successful trying to read them using the same method that I do other workout HKQuantityTypes (heartRate, stepCount, etc). I'm using Swift and I do have authorization for those types requested and granted. I have found documentation on setting these values (https://developer.apple.com/forums/thread/763539) but not reading them. Thank You
2
0
936
Jan ’25
Workouts fail to register on Fitness activity rings
Hello, My app syncs workout data from a third-party device and records workouts with HealthKit as follows: let builder = HKWorkoutBuilder(healthStore: healthStore, configuration: hkConf, device: hkDevice) try await builder.beginCollection(at: startDate) try await builder.addSamples(samples) try await builder.endCollection(at: endDate) let workout = try await builder.finishWorkout() let workoutRouteBuilder = HKWorkoutRouteBuilder(healthStore: healthStore, device: hkDevice) try await workoutRouteBuilder.insertRouteData(filteredLocations) try await workoutRouteBuilder.finishRoute(with: workout, metadata: nil) However, I’m encountering two issues: The workouts appear in Apple Fitness but do not contribute to the activity rings. The workout includes a route (visible in the raw workout data in Apple Health) but does not display on Apple Fitness. Is there any way to fix this? I’d appreciate any suggestions you might have. __
2
0
768
Jan ’25
Extended Runtime Session vs HKWorkoutSession Issues
I am working on an Apple Watch companion app to an existing live iOS app. I am utilizing the heart rate tracking for an active 'self-care' sauna session. I say self-care in quotes because it's more self-care than a workout activity, but it is closely blurring the lines between the two. I have come to understand that if a session truly isn't a workout, then you should not use workoutSession.startActivity. However the app needs to function entirely like a workout would. This is not a meditation application. Sauna is actually just one of many activity types supported in the app. I have tried using extended runtime session, and there have been numerous issues with doing so. It is not nearly as robust for the user. For example, the active session is not prioritized by the watch's CPU. Now playing is no longer functional. Heart rate is far more inconsistent, and this variable is as critical as if it were in a workout. I have tried using HKWorkoutSession, however I worry the app will be rejected by doing so. This method works most accurately to collect the right data for the user, and prioritizes system resources as expected. The app can be moved to the background as expected and continue to communicate with the iOS app. What is the best way to move forward here. It almost feels like I am operating in a grey area with no real solution in place. Any assistance is greatly appreciated as we would like to follow all guidelines while producing a high quality experience for our users.
2
0
816
Jan ’25
Location of indoor workouts
In the fitness app under iOS 18, the location of all workouts is displayed on a small map. For workouts with routes, I can already successfully read out the route and thus also determine the starting point. So that works. For indoor workouts such as yoga or indoor rowing, the exact location is also displayed in the fitness app. I would now also like to read out this location for these indoor workouts in my app. Does anyone know how to do this?
2
0
826
Apr ’25
怎样读取健康记录心理状态的情境,并将自己APP的数据传入进去
读取是不是解析 metadata 的对应键来获取值对吧~但我看了相关开发文档好像没找到这个的键是什么~于是也没法写入到对应的,现在只能自定义键来进行写入 但是这样写入后无法显示在心情下方的影响因素后面~ 这个 key 是没公开的吗还是说我方法弄错了~请各位大大指教
2
0
90
May ’25
Statistics collection query first result returned is wrong
I'm reading hourly statistics from HealthKit using executeStatisticsCollectionQuery (code below). Expectation What I expect is to get back the list with one row per hour, where each hours has the same cumulative sum value. Actual result In results, first hour always contains less calories than next hours, which all have the same value. Example: Start: 2025-06-02T00:00:00+03:00, anchor: 2025-06-02T00:00:00+03:00, end: 2025-06-02T12:00:00+03:00 🟡 2025-06-02T00:00:00+03:00 Optional(50.3986 kcal) 🟡 2025-06-02T01:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T02:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T03:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T04:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T05:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T06:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T07:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T08:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T09:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T10:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T11:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T12:00:00+03:00 Optional(14.0224 kcal) As you can see, here we have 2025-06-02T00:00:00+03:00 Optional(50.3986 kcal) Now, if I add one more hour to the request (from beginning of time window), the same hour has proper calories count, while newly added hour, has wrong value): 2025-06-01T23:00:00+03:00, anchor: 2025-06-01T23:00:00+03:00, end: 2025-06-02T12:00:00+03:00. 🟡 2025-06-01T23:00:00+03:00 Optional(50.3986 kcal) 🟡 2025-06-02T00:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T01:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T02:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T03:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T04:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T05:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T06:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T07:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T08:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T09:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T10:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T11:00:00+03:00 Optional(64.421 kcal) 🟡 2025-06-02T12:00:00+03:00 Optional(14.0224 kcal) And now first hour of the day, magically has more calories burned: 2025-06-02T00:00:00+03:00 Optional(64.421 kcal) I suspect similar things happen with other quantity types, but haven't yet found a way to reproduce it. Am I doing something wrong or is it a bug in HealthKit? Code let anchorDate = startDate let predicate = HKQuery.predicateForSamples(withStart: startDate, end: endDate, options: [.strictStartDate]) healthStore.executeStatisticsCollectionQuery( quantityType: .basalEnergyBurned, quantitySamplePredicate: predicate, options: [.separateBySource, .cumulativeSum], anchorDate: anchorDate, intervalComponents: DateComponents(hour: 1), initialResultsHandler: { statistics, error in if let error = error { log(.error, "Error retrieving steps: \(error.localizedDescription)") continuation.resume(throwing: SpikeException("Error retrieving steps: \(error.localizedDescription)")) return } if let statistics { let f = ISO8601DateFormatter() f.timeZone = TimeZone.current for s in statistics { log(.debug, "\(f.string(from: s.startDate)) \(s.sumQuantity())") } } continuation.resume(returning: statistics ?? []) } )
2
0
97
Jul ’25
What’s the expected frequency of HealthKit enableBackgroundDelivery: HKCategoryTypeIdentifier.sleepAnalysis
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!
2
2
236
Sep ’25
Guideline 1.4.1 - Safety - Physical Harm
Hello everyone, my app is designed to help people sleep. It has been rejected multiple times due to issues with version 1.4.1 during the submission process. However, the app simply evaluates users’ insomnia and anxiety status based on their responses to questions and provides some relaxation methods. It does not involve any medical-related content. The reviewer provided screenshots of the assessment results page and some relaxation techniques. How should I handle this issue?
2
0
153
Jun ’25
Support for cycling power & cadence sensors in HKWorkoutSession on iOS?
Hi everyone, while testing HKWorkoutSession with HKLiveWorkoutBuilder on iOS 26 Beta (cycling workout), I noticed the following behavior: – Starting a cycling HKWorkoutSession automatically connects to my Bluetooth heart rate monitor and records HR into HealthKit ✅ – However, my Bluetooth cycling power meter and cadence sensor (standard BLE Cycling Power & CSC services) are not connected automatically, and no data is recorded into HealthKit ❌ On Apple Watch, when starting a cycling workout, these sensors do connect automatically and their data is written to HealthKit — which is exactly what I would expect on iOS as well. Question: Is this by design, or is support for power and cadence sensors planned for iOS in the same way as on watchOS? Or do we, as developers, need to implement the BLE Cycling Power and CSC profiles ourselves (via CoreBluetooth) if we want these metrics? Environment: – iOS 26 Beta – HKWorkoutSession & HKLiveWorkoutBuilder (cycling) – Bluetooth HRM connects automatically – BLE power & cadence sensors do not This feature would make it much easier to develop cycling apps with full HealthKit integration, and also create a more consistent user experience compared to watchOS. Thanks for any insights!
2
1
141
Jul ’25
HKObserverQuery and BackgroundDelivery Are Highly Unstable on watchOS 26
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.
2
0
188
Oct ’25
Icon Composer - Icon not visible in Fitness App
Hi everyone, we’re developing an app that lets users export selected bike rides to the HealthKit ecosystem. We created our app icon using the Apple Icon Composer and referenced the composer file in Xcode. Everything works fine, except that the logo doesn’t appear correctly in the Fitness app. Has anyone experienced this issue or knows how to fix it?
2
1
123
Nov ’25
Recording a HeartbeatSeries
I need to be able to create and store a HeartbeatSeries for a given time-period from an Apple Watch, to then retrieve that data from HealthKit to be processed. I have working code which allows me to begin a workout session, which is being used to determine how long a session has been running for. I also have working code for retrieving HeartbeatSeries data from HealthKit. The issue is that no HeartbeatSeries data is being stored into HealthKit as a result of the workout session running. Whether that session is running for as little as 30 seconds or as long as 20 minutes, nothing is stored. However, when I use the the Apple "Meditation" app (formerly known as "Breathe"), I can query HealthKit afterwards and retrieve a list of individual heartbeat timings during that 2 minute period. Therefore, it IS possible to store a HeartbeatSeries from within an app on the Apple Watch. What I would like to know is, how can I use the pulse sensor built-in to the Apple Watch to be able to record a HeartbeatSeries similar to how the Meditation app does it.
3
0
117
Mar ’25
How to run HKWorkoutSession on watch without affecting activity rings?
My research group is using watch sensors (accelerometers, gyroscopes) to track wrist motion to detect and measure eating. https://cecas.clemson.edu/ahoover/bite-counter/ We are running an HKWorkoutSession on the watch so that the app can run for an extended period of time (up to 12 hr) and continue to sense and process motion data. Our app is adding to the activity rings, making it look like the user is exercising the entire time our app is running. Is there a method to prevent our app from contributing to the activity ring measures?
3
0
129
Apr ’25
UIScene.ConnectionOptions.shouldHandleActiveWorkoutRecovery Missing?
According to the WWDC25 Presentation Track workouts with HealthKit on iOS and iPadOS, there is supposed to be a new property for restoring an active workout after a crash on iOS/iPadOS. The developer documentation also supports this. However, this property does not seem to exist in the latest Xcode 26 beta, even in projects targeting iOS 26.0 as the minimum version. Am I missing something? Has this property not been made available yet? It is actually looking like all of the new iOS 26.0 properties are missing UIScene.ConnectionOptions on my system.
3
0
182
Aug ’25
Sleep Score API access
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).
3
1
229
Sep ’25
How to accurately query HKWorkout segment data
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.
3
0
128
Oct ’25