HealthKit is a framework for iOS and watchOS that allows health and fitness services to share their data with the new Health app and with each other.
HealthKit allows apps that provide health and fitness services to share their data with the new Health app and with each other. A user’s health information is stored in a centralized and secure location and the user decides which data should be shared with your app.
HealthKit also works directly with health and fitness devices. In iOS 8.0, the system can automatically save data from compatible Bluetooth LE heart rate monitors directly into the HealthKit store. The system can also automatically import step count data from the M7 motion coprocessor, if available. Other devices and data sources must have a companion app that can access the data and save it to HealthKit for them.
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