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 ?? [])
}
)
Health & Fitness
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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!
Hi guys,
We have an app that consumes data from Apple HealthKit. We use an HKObserverQuery to monitor changes in HealthKit data, and occasionally use regular HKSampleQuery requests when the app is in the foreground.
Over the past few weeks, we’ve been encountering a significant number of errors when requesting additional HealthKit permissions (beyond what the user has already granted). The error message we’re seeing is:
The operation couldn't be completed. (_UIViewServiceInterfaceErrorDomain error 2.)
When this error occurs, all previously granted HealthKit permissions are automatically revoked, which is highly disruptive.
We have a few questions and would greatly appreciate any insights or explanations regarding this behavior:
Could this error occur if a permission request is triggered right as the app moves to the background?
Why would previously granted permissions be revoked automatically after this error?
If this is due to some internal behavior in iOS (e.g., a system-level protection or timeout), is there any known workaround or best practice to prevent this from happening?
Thanks in advance for your help!
Hello. I have implemented background delivery for detecting changes in health kit with HKObserverQuery. It works well, I am reading changes. And I am sending this changes to an https endpoint with using an URLSession.shared.dataTask inside the HKObserverQuery callback while my app is terminated. I have several questions about this:
Is starting a URLSession.shared.dataTask inside HKObserverQuery callback when app is terminated is correct way to do it?
I am calling HKObserverQuery completion handler whatever dataTask returned success or failure but I am wondering what if the network connection is low and this dataTask response could not received in 2-3 seconds. I have read background deliveries should take 1-2 seconds. Should I use an URL session with background configuration for sending those HTTPS requests? If so, should I use download task or upload task (they don't fit my requirements I am sending a simple json)?
Overview of Issue
My implementation of HealthKit is no longer able to read values due to authorization issues (ex. "HealthKitService: Not authorized to read HKQuantityTypeIdentifierHeight. Status: 0"). I have been through every conceivable debugging step including building a minimal project that just requests HealthKit data and the issue has persisted. I've tried my personal as well as Organizational developer teams. My MacOS and Mac Mini. Simulator and personal device. Rechecked entitlements, reprovisioned certificates. This makes no sense. And I have been unable to find anything similar in the Developer forums or documentation.
The problem occurs during the onboarding flow when the app requests HealthKit permissions. Even when the user grants permission in the HealthKit authorization sheet, the authorizationStatus for characteristic data types (like Biological s3x and Date of Birth) and quantity data types (like Height and Weight) consistently returns as .sharingDenied. This prevents the app from pre-filling the user's profile with their HealthKit data, forcing them to enter it manually.
The issue seems to be environmental rather than a specific code bug, as it has been reproduced in a minimal test case app and persists despite extensive troubleshooting.
Minimal test project: https://github.com/ChristopherJones72521/HealthKitTestApp**
STEPS TO REPRODUCE
Build app, attempt to sign in. No data is imported into the respective fields in the main app. Console logs confirm.
PLATFORM AND VERSION
iOS
Development environment: Xcode Version 16.4 (16F6), macOS 15.5 (24F74)
Run-time configuration: iOS 18.5
Relevant Code Snippets
Here are the key pieces of code that illustrate the implementation and the problem:
1. Requesting HealthKit Permissions (HealthKitService.swift)
This function is called to request authorization for the required HealthKit data types. The typesToRead and typesToWrite are defined in a centralized HealthKitTypes struct.
// HealthKitService.swift
func requestPermissions(completion: @escaping (Bool, Error?) -> Void) {
guard HKHealthStore.isHealthDataAvailable() else {
completion(false, HealthKitError.notAvailable)
return
}
let typesToRead: Set<HKObjectType> = [
HKObjectType.characteristicType(forIdentifier: .dateOfBirth)!,
HKObjectType.characteristicType(forIdentifier: .biologicals3x)!,
HKObjectType.quantityType(forIdentifier: .height)!,
HKObjectType.quantityType(forIdentifier: .bodyMass)!
]
let typesToWrite: Set<HKSampleType> = [
HKObjectType.workoutType(),
HKObjectType.quantityType(forIdentifier: .activeEnergyBurned)!
]
healthStore.requestAuthorization(toShare: typesToWrite, read: typesToRead) { success, error in
DispatchQueue.main.async {
if let error = error {
print("HealthKitService: Error requesting authorization: \(error.localizedDescription)")
completion(false, error)
} else {
print("HealthKitService: Authorization request completed. Success: \(success)")
completion(success, nil)
}
}
}
}
2. Reading Biological s3x (HealthKitService.swift)
This function attempts to read the user's biological s3x. The print statements are included to show the authorization status check, which is where the issue is observed.
// HealthKitService.swift
func readBiologicals3x() async throws -> HKBiologicals3xObject? {
guard HKHealthStore.isHealthDataAvailable() else { throw HealthKitError.notAvailable }
let s3xAuthStatus = healthStore.authorizationStatus(for: HKObjectType.characteristicType(forIdentifier: .biologicals3x)!)
print("HealthKitService: Auth status for Biological s3x: \(s3xAuthStatus.rawValue)")
guard s3xAuthStatus == .sharingAuthorized else {
print("HealthKitService: Not authorized to read Biological s3x.")
throw HealthKitError.notAuthorized
}
do {
return try healthStore.biologicals3x()
} catch {
print("HealthKitService: Error executing biologicals3x query: \(error.localizedDescription)")
throw HealthKitError.queryFailed(error)
}
}
3. Calling HealthKit Functions During Onboarding (OnboardingFlowView.swift)
This is how the HealthKitService is used within the onboarding flow. The requestHealthKitAndPrefillData function is called after the user signs in, and it attempts to read the data to pre-fill the profile form.
// OnboardingFlowView.swift
func readHealthKitDataAsync() async {
print("Attempting to read HealthKit data async...")
// ... (calls to HealthKitService.shared.readDateOfBirth(), readHeight(), etc.)
do {
if let biologicals3xObject = try await HealthKitService.shared.readBiologicals3x() {
if self.selectedGender == nil {
switch biologicals3xObject.biologicals3x {
case .female: self.selectedGender = .female
case .male: self.selectedGender = .male
case .other: self.selectedGender = .other
default:
break
}
}
}
} catch {
print("OnboardingFlowView: Error reading Biological s3x: (error.localizedDescription)")
}
print("OnboardingFlowView: Finished HealthKit data processing.")
}
Console Logs
Attempting to read HealthKit data async...
HealthKitService: Reading Date of Birth...
HealthKitService: Current auth status for DOB (during read attempt): 0
HealthKitService: Not authorized to read Date of Birth. Status: 0
OnboardingFlowView: Error reading Date of Birth: The operation couldn’t be completed. (Strike_Force.HealthKitError error 2.)
HealthKitService: Reading Height...
HealthKitService: Current auth status for HKQuantityTypeIdentifierHeight (during read attempt): 0
HealthKitService: Not authorized to read HKQuantityTypeIdentifierHeight. Status: 0
OnboardingFlowView: Error reading Height: The operation couldn’t be completed. (Strike_Force.HealthKitError error 2.)
HealthKitService: Reading Weight (Body Mass)...
HealthKitService: Current auth status for HKQuantityTypeIdentifierBodyMass (during read attempt): 0
HealthKitService: Not authorized to read HKQuantityTypeIdentifierBodyMass. Status: 0
OnboardingFlowView: Error reading Weight: The operation couldn’t be completed. (Strike_Force.HealthKitError error 2.)
HealthKitService: Pre-read check for Biologicals3x auth status: 1 (Denied)
HealthKitService: Reading Biological s3x...
HealthKitService: Current auth status for Biological s3x (during read attempt): 1
HealthKitService: Not authorized to read Biological s3x. Status: 1
OnboardingFlowView: Error reading Biological s3x: The operation couldn’t be completed. (Strike_Force.HealthKitError error 2.)
watchos 26 新增了睡眠评分,开发者如何获取这个评分,有相关的文档和API吗?
Watchos 26 has added a sleep rating. How can developers obtain this rating? Do you have any relevant documentation and APIs?
Topic:
App & System Services
SubTopic:
Health & Fitness
I have recently come across a couple of odd HealthKit step samples from WatchOS. They represent step data measured in 2022 by my Apple Watch, but they have a creation date ("Date Added to Health") within the past couple of days. These odd samples show a "View All Quantities" button at the bottom of the sample Details page in the Health app on iOS 26 (which I've never seen before); the button leads to a list of many small step quantities, almost as if some older, smaller samples were consolidated into these newer samples.
Even weirder is that at least some of these samples seem to be getting re-created repeatedly. For example, I've seen the same sample with a "Date Added to Health" of 9/5/25, then 9/8/25, twice on 9/9/25, and twice on 9/10/25.
These samples were originally created by WatchOS 9, and are not being deleted/recreated by any apps on my device. I have only observed it since I updated to the iOS 26 beta (and now the RC); my watch was still running iOS 18 the first time it happened, but it has also happened since my watch was updated to WatchOS 26 beta.
I did some debug printing of the odd samples and the normal samples surrounding them for comparison.
Here's a normal sample:
Sample: 80AC5AC5-CBD7-4581-B275-0C2ACA35B7B4 6 count 80AC5AC5-CBD7-4581-B275-0C2ACA35B7B4, (9.0), "Watch6,1" (9.0) "Apple Watch" (2022-09-15 16:20:14 -0500 - 2022-09-15 16:20:16 -0500)
Device: <<HKDevice: 0x10591eee0>, name:Apple Watch, manufacturer:Apple Inc., model:Watch, hardware:Watch6,1, software:9.0, creation date:2022-08-25 18:22:26 +0000>
Source revision: <HKSourceRevision name:My Apple Watch, bundle:com.apple.health.EE83959D-D009-4BA0-83A5-2E5A1CC05FE6, version:9.0, productType:Watch6,1, operatingSystemVersion:9.0>
Source: <HKSource:0x110588690 "My Apple Watch", bundle identifier: com.apple.health.EE83959D-D009-4BA0-83A5-2E5A1CC05FE6, localDeviceSource: 0, modification date: 2024-01-31 05:49:18 +0000>
Date added: 2022-09-15 21:20:16 +0000
Days between end and add: 0
And here's one of the odd samples:
Sample: 4982487F-1189-4F16-AB00-61E37818A66D 676 count 4982487F-1189-4F16-AB00-61E37818A66D, (9.0), "iPhone12,1" (16.2) "Apple Watch" metadata: {
HKMetadataKeySyncIdentifier = "6:38082859-D9C8-466A-8882-53443B2A2D94:684969619.25569:684970205.31182:119";
HKMetadataKeySyncVersion = 1;
} (2022-09-15 16:20:19 -0500 - 2022-09-15 16:30:05 -0500)
Device: <<HKDevice: 0x10591ce40>, name:Apple Watch, manufacturer:Apple Inc., model:Watch, hardware:Watch6,1, software:9.0, creation date:2022-08-25 18:22:26 +0000>
Source revision: <HKSourceRevision name:My Apple Watch, bundle:com.apple.health.EE83959D-D009-4BA0-83A5-2E5A1CC05FE6, version:9.0, productType:iPhone12,1, operatingSystemVersion:16.2>
Source: <HKSource:0x110588640 "My Apple Watch", bundle identifier: com.apple.health.EE83959D-D009-4BA0-83A5-2E5A1CC05FE6, localDeviceSource: 0, modification date: 2024-01-31 05:49:18 +0000>
Date added: 2025-09-08 21:11:12 +0000
Days between end and add: 1088
Here's that same odd sample a day later, apparently recreated:
Sample: 9E8B12FC-048D-4ECD-BE5B-D387AADE5130 676 count 9E8B12FC-048D-4ECD-BE5B-D387AADE5130, (9.0), "iPhone12,1" (16.2) "Apple Watch" metadata: {
HKMetadataKeySyncIdentifier = "6:38082859-D9C8-466A-8882-53443B2A2D94:684969619.25569:684970205.31182:119";
HKMetadataKeySyncVersion = 1;
} (2022-09-15 16:20:19 -0500 - 2022-09-15 16:30:05 -0500)
Device: <<HKDevice: 0x12f01c4e0>, name:Apple Watch, manufacturer:Apple Inc., model:Watch, hardware:Watch6,1, software:9.0, creation date:2022-08-25 18:22:26 +0000>
Source revision: <HKSourceRevision name:My Apple Watch, bundle:com.apple.health.EE83959D-D009-4BA0-83A5-2E5A1CC05FE6, version:9.0, productType:iPhone12,1, operatingSystemVersion:16.2>
Source: <HKSource:0x12f0f8230 "My Apple Watch", bundle identifier: com.apple.health.EE83959D-D009-4BA0-83A5-2E5A1CC05FE6, localDeviceSource: 0, modification date: 2024-01-31 05:49:18 +0000>
Date added: 2025-09-09 20:53:18 +0000
Days between end and add: 1089
It's worth pointing out some differences between the "normal" and "odd" samples (besides the "View All Quantities" button in the Health app). The recreated "odd" samples have a different Source Revision - the "productType" and "operatingSystemVersion" refer to my iPhone, not the Apple Watch device that actually captured the samples. The odd samples also have metadata keys that don't exist in the other samples - HKMetadataKeySyncIdentifier and HKMetadataKeySyncVersion.
Questions I'm hoping someone can help with:
What are these samples? Why/how do they have a "View All Quantities" button that shows sub-samples?
Is this new to iOS 26?
Why are some of the samples getting recreated multiple times?
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.
Can’t get the live data from ppg sensor (se os 26.x) for 0 latency parsing of haptics per each pulse (heart beat). any help would be cool.
b
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?
Topic:
App & System Services
SubTopic:
Health & Fitness
Tags:
Health and Fitness
HealthKit
Icon Composer
The second time i start a workout session, the beginCollection instance method on HKLiveWorkoutBuilder freezes.
To recreate run the Apple Sample Project Building a multidevice workout app. It looks like a bug with the HealthKit SDK and not the code but i could be wrong. The only workaround i found was erasing the simulator and reinstalling the app.
Hi!
I have over 800 days strike in closing my move circle. However oerfect month badge is not popping up for November, we have now mid of Dec and still no update.
I updated iOS to 26, did multiple resets and hard resets and still no badge. I checked many forums and post but any of given tips is working in my case.
i know it sounds funny, but it’s frustrating that I’m not getting this little gold medal to keep me motivated 😅
does anyone know how to deal with it? Is it common issue?
Hello everyone,
I’m experiencing a visual issue when dismissing a sheet on iOS 26.
I’m using the same implementation shown in the official Apple documentation. While testing, I noticed that some apps do not exhibit this behavior. However, when running this code on iOS 26, the issue consistently occurs.
Issue description:
The sheet dismisses abruptly
A white screen briefly appears for a few milliseconds and then disappears
This results in a noticeable visual glitch and a poor user experience
I tested the exact same code on iOS 18, where the sheet dismisses smoothly and behaves as expected, without any visual artifacts.
Has anyone else encountered this issue on iOS 26?
Is this a known bug, or is there a recommended workaround?
Any insights would be greatly appreciated.
Thank you.
How do I add my hospital to the list of hospitals available on the Health Records on iPhone application?
I have FB12696743 open since July 21, 2023 and this happened again today.
I get home at approx 10 mins after the hour, walk appox 50 ft across my yard, up 5 steps into my house, let the dog out and pace on my deck watching the dog, go back in the house walk around the kitchen while preparing dinner. A total of about 200 ft. I sit down about 35 past the hour and start to eat and at 10 mins to the next our and I get the reminder to stand.
On the other side I wake up at 5 mins to hour. Walk 8 steps to the bathroom and successfully achieve the stand for that hour.
WHY!?!?!? 😁🤣
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?
Hello, we want to re-create these graphs and use the raw data for analysis.
We are getting aggregated elevation, heath rate, and pace data, but need to locate the specifics to create these graphs.
Thank you
Topic:
App & System Services
SubTopic:
Health & Fitness
Good afternoon,
I am working on a workout tracking app. So far everything is working as expected. However, I note that when my workout saves and is visible within the Fitness App, the workout duration is displayed rather than the kCal burned.
What changes are required to be made in order for this to display the kCal in the list of workouts in Fitness rather than duration?
For reference https://developer.apple.com/videos/play/wwdc2021/10009 this was my reference source for workout functionality.
I have a workout app which I am testing on device currently via TestFlight.
The generated workout (tennis and indoor) shows in the fitness app with correct HR and duration.
However, when I go to my Strava app, it does not show in the list of workouts for importing. (note, activities tracked using the regular tennis mode on the Apple Watch show fine)
I have also concurrently reached out to Strava support to see if there's anything they can offer support for.
However, does anybody here have any knowledge/experience of the requirement? Or whether this is a limitation of an application deployed via TestFlight?
I have a terrible feeling I am chasing ghosts, and it may be a TestFlight limitation for exporting workouts?
Thanks
Topic:
App & System Services
SubTopic:
Health & Fitness
Tags:
Health and Fitness
HealthKit
TestFlight
In my WatchOS app I've written the following code to check if my app has access to the user's health data:
func isHealthKitAuthorized() -> Bool {
let typesToRead: [HKObjectType] = [
HKObjectType.quantityType(forIdentifier: .heartRate)!,
HKObjectType.quantityType(forIdentifier: .activeEnergyBurned)!,
HKObjectType.quantityType(forIdentifier: .appleMoveTime)!,
HKObjectType.quantityType(forIdentifier: .appleExerciseTime)!,
HKObjectType.workoutType()
]
let typesToShare: Set<HKSampleType> = [
HKObjectType.workoutType(),
HKObjectType.quantityType(forIdentifier: .activeEnergyBurned)!,
HKObjectType.quantityType(forIdentifier: .heartRate)!
]
var isAuthorized = true
for type in typesToRead {
let status = healthStore.authorizationStatus(for: type)
if status != .sharingAuthorized {
print("Access denied to: \(type.identifier)")
isAuthorized = false
}
}
for type in typesToShare {
let status = healthStore.authorizationStatus(for: type)
if status != .sharingAuthorized {
print("Access denied to: \(type.identifier)")
isAuthorized = false
}
}
return isAuthorized
}
However for the appleMoveTime and appleExerciseTime types their status is returning as 'sharingDenied' (checked by printing the status' rawValue) even though they are authorized on the Watch's settings. This happened both on the simulator and on the Watch itself. Am I doing something wrong?