How to use the Apple Health app and HealthKit

Mostly because of the Apple Watch, Apple Health and HealthKit have become a pretty integral part of owning an iPhone. If you’re new to them, though, they can be a little overwhelming, and it may not be clear why they matter at all if you have a third-party fitness tracker with its own app. This guide will fill you in on all the essential details, including the basics of how to use the Health app.