'Further Manufacturer's Details (for this range)...Model: Fitbit Zip Tracks steps, distance and calories burned Syncs automatically to your computer or select mobile devices via Bluetooth 4 Set goals, view progress and earn badges Share and compete with friends throughout the day Free iPhone and Android App Small and discreet â€" wear in pocket, on belt or bra Log food, weight and more on Fitbitâ€TMs website or apps Sweat, rain and splash proof Replaceable battery with a 4-6-month life Contents: Fitbit Zip, clip, battery, battery tool