What's the use of HealthKit in IPHONE?
HealthKit means that you can use different companies' devices and applications-for example, a Nike FuelBand, a sphygmomanometer with Withings, and an iHealth wireless intelligent blood glucose monitoring system-and all the data will be integrated into Apple's health application, which will let you know your overall health. There can also be communication between different applications. For example, if a nutrition application is synchronized with a health application, it will tell you how many calories you need to burn to lose 1 pound.