watchOS 27, launching this fall, introduces 'proactive battery extension notifications' to enhance Apple Watch battery life. This new feature detects and offers to disable unused background features like gestures, Raise to Speak for Siri, and Start Workout reminders, which can consume power.

If watchOS 27 identifies features you don't regularly use, it will send an alert informing you of the automatic disabling to save battery. Users will have the option to keep these features enabled if they prefer. While Apple hasn't specified the exact battery savings, the implementation suggests the power conservation is significant.

Beyond battery improvements, watchOS 27 also adds two new apps, a tap gesture, a revised Home Screen, and three health-related upgrades. The focus on battery optimization through intelligent feature management marks a key development in the upcoming update.