atA new generation of Apple Watch(and the brand new Apple Watch Ultra) Existing Apple Watch owners will be able to upgrade to watchOS 9 first, ahead of the market launch later this month.Apple announced watchOS 9 It will go live on September 12th, the same day as iOS 16. To install watchOS 9, in addition to having an iPhone 8 or iPhone SE or newer, the watch itself must be an Apple Watch Series 4 or newer generation, and the Apple Watch Series 3 unfortunately cannot be upgraded.
The main new features of watchOS 9 include analyzing the user’s various postures while running, including “step length”, “touchdown time” and “vertical amplitude”, etc., as well as a new sleep tracking function, which will use the accelerometer and heart rate sensor. The data of the monitor is used to analyze the user’s time in rapid eye movement (REM), core sleep, and deep sleep. Others include medication reminders, a new Siri, an improved calendar app, and more, but not all generations of Apple Watch or all countries where they are sold will have the same features.