@kingstinct/react-native-healthkit

React Native bindings for HealthKit with full TypeScript and Promise support covering about any kind of data. Keeping TypeScript mappings as close as possible to HealthKit - both in regards to naming and serialization. This will make it easier to keep this library up-to-date with HealthKit as well as browsing the official documentation (and if something - metadata properties for example - is not typed it will still be accessible).

Disclaimer

This library is provided as-is without any warranty and is not affiliated with Apple in any way. The data might be incomplete or inaccurate.

Installation

Expo

Usage with Expo is possible - just keep in mind it will not work in Expo Go and you'll need to roll your own Dev Client.

1. yarn add @kingstinct/react-native-healthkit
2. Update your app.json with the config plugin:

{
  "expo": {
    "plugins": ["@kingstinct/react-native-healthkit"]
  }
}

this will give you defaults that make the app build without any further configuration. If you want, you can override the defaults:

{
  "expo": {
    "plugins": [
      ["@kingstinct/react-native-healthkit", {
        "NSHealthShareUsageDescription": "Your own custom usage description",
        "NSHealthUpdateUsageDescription": false,  // if you have no plans to update data, you could skip adding it to your info.plist
        "background": false // if you have no plans to use it in background mode, you could skip adding it to the entitlements
      }]
    ]
  }
}

3. Build a new Dev Client

Native or Expo Bare Workflow

1. yarn add @kingstinct/react-native-healthkit
2. npx pod-install
3. Set NSHealthUpdateUsageDescription and NSHealthShareUsageDescription in your Info.plist
4. Enable the HealthKit capability for the project in Xcode.
5. Since this package is using Swift you might also need to add a bridging header in your project if you haven't already, you can find more about that in the official React Native docs

Usage

During runtime check and request permissions with requestAuthorization. Failing to request authorization, or requesting a permission you haven't requested yet, will result in the app crashing. This is easy to miss - for example by requesting authorization in the same component where you have a hook trying to fetch data right away.. :)

Some hook examples:

import { HKQuantityTypeIdentifier, useHealthkitAuthorization } from '@kingstinct/react-native-healthkit';

const [authorizationStatus, requestAuthorization] = useHealthkitAuthorization([HKQuantityTypeIdentifier.bloodGlucose])

// make sure that you've requested authorization before requesting data, otherwise your app will crash
import { useMostRecentQuantitySample, HKQuantityTypeIdentifier, useMostRecentCategorySample } from '@kingstinct/react-native-healthkit';

const mostRecentBloodGlucoseSample = useMostRecentQuantitySample(HKQuantityTypeIdentifier.bloodGlucose)
const lastBodyFatSample = useMostRecentQuantitySample(HKQuantityTypeIdentifier.bodyFatPercentage)
const lastMindfulSession = useMostRecentCategorySample(HKCategoryTypeIdentifier.mindfulSession)
const lastWorkout = useMostRecentWorkout()

Some imperative examples:

  import HealthKit, { HKUnit, HKQuantityTypeIdentifier, HKInsulinDeliveryReason, HKCategoryTypeIdentifier } from '@kingstinct/react-native-healthkit';

  const isAvailable = await HealthKit.isHealthDataAvailable();

  /* Read latest sample of any data */
  await HealthKit.requestAuthorization([HKQuantityTypeIdentifier.bodyFatPercentage]); // request read permission for bodyFatPercentage

  const { quantity, unit, startDate, endDate } = await HealthKit.getMostRecentQuantitySample(HKQuantityTypeIdentifier.bodyFatPercentage); // read latest sample
  
  console.log(quantity) // 17.5
  console.log(unit) // %

  /* Listen to data */
  await HealthKit.requestAuthorization([HKQuantityTypeIdentifier.heartRate]); // request read permission for heart rate

  const unsubscribe = HealthKit.subscribeToChanges(HKQuantityTypeIdentifier.heartRate, () => {
    // refetch whichever queries you need
  });

  /* write data */
  await HealthKit.requestAuthorization([], [HKQuantityTypeIdentifier.insulinDelivery]); // request write permission for insulin delivery

  ReactNativeHealthkit.saveQuantitySample(
      HKQuantityTypeIdentifier.insulinDelivery,
      HKUnit.InternationalUnit,
      5.5,
      {
        metadata: {
          // Metadata keys could be arbirtary string to store app-specific data.
          // To use built-in types from https://developer.apple.com/documentation/healthkit/samples/metadata_keys
          // you need to specify string values instead of variable names (by dropping MetadataKey from the name).
          HKInsulinDeliveryReason: HKInsulinDeliveryReason.basal,
        },
      }
    );

HealthKit Anchors (breaking change in 6.0)

In 6.0 you can use HealthKit anchors to get changes and deleted items which is very useful for syncing. This is a breaking change - but a very easy one to handle that TypeScript should help you with. Most queries now return an object containing samples which is what was returned as only an array before. In addition you also get deletedSamples and a newAnchor you can use for more advanced use cases, example:

  const { newAnchor, samples, deletedSamples } = await queryQuantitySamples(HKQuantityTypeIdentifier.stepCount, {
    limit: 2,
  })

  const nextResult = await queryQuantitySamples(HKQuantityTypeIdentifier.stepCount, {
    limit: 2,
    anchor: newAnchor,
  })

  // etc..

A note on Apple Documentation

We're striving to do as straight a mapping as possible to the Native Libraries. This means that in most cases the Apple Documentation makes sense. However, when it comes to the Healthkit Metadata Keys the documentation doesn't actually reflect the serialized values. For example HKMetadataKeyExternalUUID in the documentation serializes to HKExternalUUID - which is what we use.

Clinical Records

For accessing Clinical Records use old version (3.x) or use specific branch "including-clinical-records". The reason is we cannot refer to this code natively in apps without getting approval from Apple, this could probably be solved by the config plugin but we haven't had time to look into it yet.

Android alternatives

For a similar library for Android, check out react-native-health-connect that works with the new Health Connect. For Google Fit react-native-google-fit seems to be the most popular option, and and another possible option is to work directly with the Google Fit REST API which I've some experience with.

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

Sponsorship and enterprise-grade support

If you're using @kingstinct/react-native-healthkit to build your production app please consider funding its continued development. It helps us spend more time on keeping this library as good as it can be.

At Kingstinct we're also able to provide enterprise-grade support for this package, find us here or drop an email for more information. Also feel free to join our Discord community.

License

MIT