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)
}
HealthKit
RSS for tagAccess and share health and fitness data while maintaining the user’s privacy and control using HealthKit.
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This is probably a basic question but I wanted to ask your advice for the best way to take consenting users' Watch data from Apple Health Kit and send it to our central server? One idea we had was to create an iOS app that gets the data from Apple's Health SDK on the phone and sends it to our server. Would appreciate any help here, thank you.
When I update a variable inside my model that is marked @Transient, my view does not update with this change. Is this normal? If I update a non-transient variable inside the model at the same time that I update the transient one, then both changes are propagated to my view.
Here is an example of the model:
@Model public class WaterData {
public var target: Double = 3000
@Transient public var samples: [HKQuantitySample] = []
}
Updating samples only does not propagate to my view.
I have a Health & Fitness widget that runs on iPhone and Apple Watch. As Health data access requires the device to be unlocked, the iPhone widget is already slightly limited in capability because of updates.
With widgets further expanding to places like CarPlay, I know I can use the .disfavouredLocations{} API to try and prevent it being offered there. This is crucial as the widget functionality would be basically non-existent as your device is locked during CarPlay use.
My problem is, on the Mac despite using the .disfavouredLocations{.iPhoneWidgetsOnMac} etc...., the widget can still be added in the "other unsupported section". And yet, in that section the Apple Fitness app widget is no where to be seen. Is there an API I am missing to completely remove a widget from the Mac widget gallery and hopefully CarPlay, Standby etc.... (all places where the device running the widget is usually locked -> No Health data)?
Or does the Apple Fitness app have a private API to block it from these places where its function is not wanted and this isn't available to other apps?
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?
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
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?
Hello,
I bumped into an issue where HealthKit functionality is optional for my library 1 only if users also add another of my libraries (library 2)
library 1: has basic functionality and using HealthKit types for some of the functions that are universal for library 1 and library 2 and using conditional checks. requirements are solid to keep it as is;
library 1 also calling functions from library 2 that have HK parameters
library 2: using basic library as a base and extending on it with HealthKit functions that library 1 can call
Is it ok to keep import HealthKit in library 1? won't it cause troubles for apps that use my library and post to AppStore?
I would like to get user's heart rate zones values in my watchOS app, is there any way to get it from HealthKit?
Furthermore, is it possible to display the Apple heart rate zones widget in my watchOS app?
I have a question about how a watch widget can access HealthKit data. Does it, as the large model mentioned, share data through an App Group, or does it directly access the HealthStore?
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?
I'm developing a medication scheduling app similar to Apple Health's Medications feature, and I'd like some input on my current approach to background tasks.
In my app, when a user creates a medication, I generate ScheduledDose objects (with corresponding local notifications) for the next 2 weeks and save them to SwiftData. To ensure this 2-week window stays current, I've implemented a BGAppRefreshTask that runs daily to generate new doses as needed.
My concern is whether BGAppRefreshTask is the appropriate mechanism for this purpose. Since I'm not making any network requests but rather generating and storing local data, I'm questioning if this is the right approach.
I'm also wondering how Apple Health's Medications feature handles this kind of scheduling. Their app seems to maintain future doses regardless of app usage patterns.
Has anyone implemented something similar or can suggest the best background execution API for this type of scenario?
Thanks for any guidance you can provide.
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
HealthKit
SwiftUI
Background Tasks
SwiftData
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 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?
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 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.
Hi everyone!
I'm trying to get the total sleep time for a given day, but users report that there's a difference between what my app reports and what the Apple Health app reports. In particular, we're off by 2 minutes less on average.
What we're doing is:
Get all the samples that are either core, deep, rem or unspecified
Cut-off time at 3 PM previous day
Merge overlapping intervals
Add all the remaining intervals
For debugging purposes I'm storing and sending all the raw samples to a server, and I have run tests and I don't find anything wrong. It looks like the number we come up with is correct according to our own rules. I wonder, how is Apple adding up all the samples to arrive at a number that's slightly off to our number.
Any insight would be appreciated. Thanks.
I have an App in objective-c that is using Health data (walk/run, cycling) to give advice to users . I do not want/need to write any data in the Healtkit.
If i do (with the 3 values in the plist / .info :
self.healthStore requestAuthorizationToShareTypes:nil readTypes:readDataTypes
My request crashes.
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Must request authorization for at least one data type'
*** First throw call stack:
(
0 CoreFoundation 0x00000001804b910c __exceptionPreprocess + 172
1 libobjc.A.dylib 0x0000000180092da8 objc_exception_throw + 72
2 CoreFoundation 0x00000001804b901c -[NSException initWithCoder:] + 0
3 HealthKit 0x000000019da034d4 -[HKHealthStore _validateAuthorizationRequestWithShareTypes:readTypes:] + 92
4 HealthKit 0x000000019da03670 -[HKHealthStore requestAuthorizationToShareTypes:readTypes:shouldPrompt:completion:] + 292
BUT in swift :
healthStore.requestAuthorization(toShare: nil, read: readTypes)
is working, présents only my 2 datas to read... in the same IOS , same phone without crashing. What is the difference ?
Nil object in objective-c and Nil object in swift are not the same ? how do i make readonly requests in objective C ?