I want to know , how many days will the data of health stays in apple watch . For example, I have not synced the watch with iPhone for two weeks . Then When I synced it , I am only able to see the last week data on iPhone of the watch . Is it true ?

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 ?? []) } )

In general my workout app is reachable from the iPhone when running a workout, even if in the background. However if the watch app restarts (due to crash or being closed via the dock) via handleActiveWorkoutRecovery then it is only reachable when in the foreground, even though a workout is running. Is this expected / desired behaviour? Is the app given a tighter sandbox (having it's "background privileges" reduced) because of the earlier crash? This behaviour occasionally happens without a crash (or being closed via the dock) - all of a sudden it is no longer reachable via the iPhone. It feels like the app is being "sandboxed" like in #1 but there is no crash or any other kind of log indicating any issue. Generally the only remedy is to stop the workout and restart the app. My question is - is this expected? Is there some condition that causes the watchOS to sandbox the app? Or is this a Watch Connectivity bug?

We are working on the health related application and use apple health kit to sync the data from different devices like watches or ring. We are targeting oura ring to get sleep and other parameters data. We are able to sync the data from oura for all other parameters (like pulse, respiratory rate, blood pressure, etc..) other than sleep. Surprisingly, sleep data that comes through other devices is syncing as expected from the health kit. We are even getting the data which is added manually in health kit. The only sleep data not syncing is from oura. Can we get a document or any kind of help to sync the data from oura in to our application using health kit?

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

Hi, i'm trying to get the number of step counts a person has taken. I decided to pull the data from health kit and the number of steps are incorrect. Come to find out apple health recommends an app called pedometer++ for the number of steps counted and after testing I realized that they are getting the correct number of steps a person is taking. How can I pull the correct number of steps a person has taken? I want to be able to merge the data from watch and phone to make sure we are getting the correct number of steps but not double counting the steps either. any guidance on this would be appreciated! Here's the code snippet that i'm using right now: permissions: { read: [AppleHealthKit.Constants.Permissions.StepCount], write: [], }, }; AppleHealthKit.initHealthKit(permissions, error => { if (error) { console.log('Error initializing HealthKit: ', error); return; } else { dispatch(setAllowHealthKit(true)); getHealthKitData(); console.log('HealthKit initialized successfully'); } }); const getHealthKitData = async () => { try { const today = new Date(); const options = { startDate: new Date(today.setHours(0, 0, 0, 0)).toISOString(), endDate: new Date().toISOString(), }; const steps = await new Promise((resolve, reject) => { AppleHealthKit.getStepCount(options, (error, results) => { if (error) reject(error); resolve(results?.value); }); }); setStepsCount(steps); } catch (error) { console.error('Error fetching HealthKit data:', error); } };

Based on Cooordinate with the companion app in this article by Apple https://developer.apple.com/documentation/healthkit/running-workout-sessions if a workout were to be started on the iPhone companion app but with no Watch available, given HKLiveWorkoutBuilder not available in iOS, does the iPhone app need to implement it's own workout tracking such as a timer for counting the elapsed time and location updates for distance and GPS tracking? If so in an instance where a paired Apple Watch were to exist and the workout is continued in the Watch app should the iPhone companion app stop this custom workout tracking and revert to the mirrored workout from the Watch to ensure accurate and synchronised data between the apps?

I'm trying to run this example project: https://developer.apple.com/documentation/HealthKit/building-a-multidevice-workout-app When I run it on my device (iPhone 16 Pro and Apple Watch Ultra 2) I get this error: -[SPRemoteInterface _appRecoverAnyExtendedRuntimeSession:]_block_invoke:4350: Got no sessions back from -[CSLSSessionService existingRunningSessions:] or -[CSLSSessionService existingScheduledSessions:] after receiving a PUICInitializeSessionServiceAction I start the workout from my phone, which successfully starts the workout on the watch. But this callback is never triggered on the phone: healthStore.workoutSessionMirroringStartHandler { // not happening } This makes it difficult to learn the mirroring workout technique. I'm using Xcode 16.3 and Mac OS 15.4.1. Any help appreciated!

For an app that plan to integrate Apple HealthKit to allow app users to upload and download their health data, where can I locate the Data Processing Addendum that specifies who the data controller and processor will be, and how such health data will be used or distributed?

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.

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?

Hello, I’m developing an iOS app that works with sleep data from Apple Watch via HealthKit. I would like to clarify the following: How can an iPhone app detect when a sleep session ends on the Apple Watch? When is sleep data typically written to the HealthKit store on iPhone after sleep ends? Is it immediately after wake-up, or does it depend on certain conditions (e.g., watch charging, connectivity)? Understanding the timing and mechanism of sleep data synchronization is crucial for our app to process accurate and timely health information. Thank you for your assistance.

Hi, I’m currently working on an app that utilizes sleep data from HealthKit to provide users with meaningful insights about their sleep. To ensure a smooth user experience, I’d like to understand when sleep data collected by the Apple Watch is saved to the HealthKit store and when it gets synced to the iPhone. Ideally, I want to fetch sleep data right after the user wakes up and opens our app. However, to do this reliably, I need to know the timing of how and when this data becomes available in the iPhone’s HealthKit store. I’ve looked through the official documentation and relevant WWDC sessions but couldn’t find clear information on this topic. If anyone has insights or experience with how and when the Apple Watch syncs HealthKit data—especially sleep records—to the iPhone, I’d greatly appreciate your input. Thanks!

I am currently developing an app that measures HRV to estimate stress levels. To align the values more closely with those from Galaxy devices, I decided not to use the heartRateVariabilitySDNN value provided by HealthKit. Instead, I extracted individual interbeat intervals (IBI) using the HKHeartBeatSeries data. Can I obtain accurate IBI data using this method? If not, I would like to know how I can retrieve more precise data. Any insights or suggestions would be greatly appreciated. Here is a sample code I tried. @Observable class HealthKitManager: ObservableObject { let healthStore = HKHealthStore() var ibiValues: [Double] = [] var isAuthorized = false func requestAuthorization() { let types = Set([ HKSeriesType.heartbeat(), HKQuantityType.quantityType(forIdentifier: .heartRateVariabilitySDNN)!, ]) healthStore.requestAuthorization(toShare: nil, read: types) { success, error in DispatchQueue.main.async { self.isAuthorized = success if success { self.fetchIBIData() } } } } func fetchIBIData() { var timePoints: [TimeInterval] = [] var absoluteStartTime: Date? let dateFormatter = DateFormatter() dateFormatter.timeZone = TimeZone(identifier: "Asia/Seoul") dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss.SSS" var calendar = Calendar.current calendar.timeZone = TimeZone(identifier: "Asia/Seoul") ?? .current var components = DateComponents() components.year = 2025 components.month = 4 components.day = 3 components.hour = 15 components.minute = 52 components.second = 0 let startTime = calendar.date(from: components)! components.hour = 16 components.minute = 0 let endTime = calendar.date(from: components)! let predicate = HKQuery.predicateForSamples(withStart: startTime, end: endTime, options: .strictStartDate) let sortDescriptor = NSSortDescriptor(key: HKSampleSortIdentifierStartDate, ascending: false) let query = HKSampleQuery(sampleType: HKSeriesType.heartbeat(), predicate: predicate, limit: HKObjectQueryNoLimit, sortDescriptors: [sortDescriptor]) { (_, samples, _) in if let sample = samples?.first as? HKHeartbeatSeriesSample { absoluteStartTime = sample.startDate let startDateKST = dateFormatter.string(from: sample.startDate) let endDateKST = dateFormatter.string(from: sample.endDate) print("series start(KST):\(startDateKST)\tend(KST):\(endDateKST)") let seriesQuery = HKHeartbeatSeriesQuery(heartbeatSeries: sample) { query, timeSinceSeriesStart, precededByGap, done, error in if !precededByGap { timePoints.append(timeSinceSeriesStart) } if done { for i in 1..<timePoints.count { let ibi = (timePoints[i] - timePoints[i-1]) * 1000 // Convert to milliseconds // Calculate absolute time for current beat if let startTime = absoluteStartTime { let beatTime = startTime.addingTimeInterval(timePoints[i]) let beatTimeString = dateFormatter.string(from: beatTime) print("IBI: \(String(format: "%.2f", ibi)) ms at \(beatTimeString)") } self.ibiValues.append(ibi) } } } self.healthStore.execute(seriesQuery) } else { print("No samples found for the specified time range") } } self.healthStore.execute(query) } }

I am trying to track a user's real-time sleep state using heart rate data, but I have encountered several issues: When using HKSampleQuery on the phone to fetch heart rate data, I can only retrieve data recorded before the app comes to the foreground or before it is terminated and restarted (see related issue: https://developer.apple.com/forums/thread/774953). I attempted to get data on the Apple Watch and send updates to the phone via Watch Connectivity. However, if I use WKExtendedRuntimeSession, although I can obtain data on the watch, once the watch screen goes off, it can no longer transmit data via Watch Connectivity to the phone (since I cannot guarantee the app will remain in the foreground when lying in bed). On the other hand, using HKWorkoutSession results in interference with the activity rings and causes the heart rate sensor to run too frequently, which I worry may affect the battery life of the watch. Is there an elegant solution for tracking a user's heart rate data for sleep monitoring?

We are developing a mobile app focused on lone worker protection, which does not include any fitness tracking features. We require the use of HKWorkoutSession solely to enable background execution of critical safety-related code. Could you please confirm whether this use of HKWorkoutSession is permitted under App Store Review guidelines, given that our app does not offer fitness or workout-related functionality?

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?

Hi, I've had trouble for a while now with HealthKit giving me different values if I make the request on iOS and WatchOS. I am using the exact same method on both with the same parameters but I get vast differences in the results. The code I am using to call HealthKit on both devices is: let dateRange = HKQuery.predicateForSamples(withStart: Date().removeMonths(numberOfMonths: 1), end: Date().endOfDay()) let predicate: NSPredicate predicate = NSCompoundPredicate(type: .and, subpredicates: [dateRange]) let query = HKStatisticsQuery(quantityType: HKQuantityType(.stepCount), quantitySamplePredicate: predicate, options: .cumulativeSum) { _, result, error in if error != nil { //print("Error fetching step count, or there is no data: \(error.localizedDescription), \(startDate) -> \(endDate)") onComplete(0) return } if let result, let sum = result.sumQuantity() { let stepCount = sum.doubleValue(for: HKUnit.count()) DispatchQueue.main.async { onComplete(Int(stepCount)) } } } healthStore.execute(query) }

For a given date, there are discrepancies between the step counts obtained from HealthKit and those displayed in the Health app. Is it possible for such discrepancies to occur even if step counts are not manually entered and multiple devices are not being used?

When we upload workout data to HealthKit the route information with the workout detailed data is incomplete: just a few dots. When we select "Show all workout routes" the route data for the same workout shows correctly. We use the HKWorkoutBuilder to store the workout data, and add the location data with the HKWorkoutRouteBuilder to the workout with Is this an Apple Health issue, or do we have to change something in the way we store the location data to the workout?