I got to look at the API docs during the first beta. I'm sure things have changed and more features have been added so take my analysis with a grain of salt. T

I got to look at the API docs during the first beta. I'm sure things have changed and more features have been added so take my analysis with a grain of salt. The HealthKit API is basically just a shared database with specific functions and structures used for measuring fitness units (e.g. time, distance, steps, heart rate, blood pressures, etc). There's a permissions model for granting read/write access to the various counters. It can also track some vitals (height, weight) and emergency contact information. And that's pretty much it. I don't think HealthKit is really designed to do more than facilitate the storage and sharing of personal fitness data. It should have been named FitnessKit.