Android is launching a new security feature that will force devices to reboot themselves if you haven’t unlocked them for a while, making it harder for other people to access the data inside. The feature included in the latest Google Play services update says that Android phones will automatically restart “if locked for 3 consecutive days,” requiring users to enter their passcode the next time they want to open the device.
https://www.theverge.com/news/648757/google-android-update-automatic-reboot-phone-locked