As of the Apple Watch Series 4 and newer, watchOS 9 will add a new Low Power Mode, as stated in a recent announcement from Apple. The Apple Watch can run for up to 36 hours on a single charge when the Low Power Mode is set.

According to Apple, Low Power Mode may temporarily disable or limit the number of sensors and capabilities, such as the always-on display, autostart workouts, heart health notifications, and more. There will still be access to other features like fall detection and activity tracking.

The Apple Watch’s Power Reserve mode, which when activated just displays the clock, is separate from the new Low Power Mode in watchOS 9.

The all-new Apple Watch Series 8 and second-generation Apple Watch SE, which are now available for pre-order and will go on sale on September 16th, 2022, will come with several new features, Low Power Mode being just one of them. The Apple Watch Series 8 also comes with a body temperature sensor tailored for women’s health as well as crash detection functionality.

About the brand-new, high-end Apple Watch Ultra, Apple announced a new battery optimization feature that will be made available later this year and will extend the device’s battery life by up to 60 hours. This feature appears to be unique from the Low Power Mode.