This builds on the original vision of HealthKit, which provided self-reported and device-recorded data to developers. Now, devs can combine that with the user's Health Records information, which Apple envisions will help manage medications, diagnose diseases and track their nutrition. This is aimed to help folks better understand their health situation, but doctors can benefit from it, too. Instead of tedious questionnaires, they can just integrate patient medical data straight into their ResearchKit study apps (after patient approval, of course).
As we knew when it was introduced, Health Records data is encrypted on the user's iOS device and protected behind their passcode. If anyone choose to share that information with third-party apps, it flows to the latter directly from HealthKit -- not through Apple's servers.
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