Apple Watch Series 9 is powered by custom Apple silicon in the all-new S9 SiP. Apple’s most powerful watch chip yet delivers systemwide improvements and brand-new features, including a new double tap gesture and on-device Siri with the ability to access and log health data privately and securely. Apple Watch Series 9 also has a new 4-core Neural Engine that can process machine learning tasks up to twice as fast, when compared with Apple Watch Series 8. The power efficiency of the S9 SiP allows Apple Watch Series 9 to maintain all-day 18-hour battery life.
The power-efficient S9 SiP and advanced display architecture increase the maximum brightness of the Apple Watch Series 9 display up to 2000 nits — double that of Series 8 — making it even easier to read text in bright sunlight. For dark rooms or early mornings, the display can also lower to just one nit so as not to disturb people close by.