Tracks steps, distance, calories, sleep and other habits; set personal goals; countdown to events Alert notifications; ring phone; control music; take photos. Non-charging, replaceable battery lasts up to 6 months (based on usage); easy to change with tool or coin White LED light display Round case with mother-of-pearl tracker disc, 26mm Bluetooth connectivity allows you to sync stats wirelessly and automatically to your Android OS 4.4+ or iPhone 5/iOS 8.2+