WatchOS 9 Brings Advanced Fitness and Sleep Tracking to Apple Watch

At its annual developers conference, Apple unveiled WatchOS 9 — a software update that quietly signals how seriously the company now regards the human body as territory worth understanding. By closing the gap between its smartwatch and specialized fitness trackers, Apple is not merely adding features; it is staking a claim that a single device on your wrist can know you as well as any dedicated instrument. The update, arriving this fall for Series 4 and newer devices, reflects a broader cultural moment in which the boundary between health care and consumer technology continues to dissolve.