Returns the shared characteristic type for the provided identifier.
- iOS 8.0+
- watchOS 2.0+
A characteristic type identifier. For a list of valid identifiers, see
HKCharacteristic instance based on the provided identifier.
This method returns an instance of the
HKCharacteristic concrete subclass. Characteristic types represent data that doesn’t typically change over time. Unlike the other object types, characteristic types cannot be used to create new HealthKit objects. Instead, users must enter and edit their characteristic data using the Health app. Characteristic types are used only when asking for permission to read data from the HealthKit store.