You can use this smart watch to make or answer calls. The watch's built-in speaker allows you to listen to your favorite music anywhere. Bluetooth dialer,pedometer,sleep monitor,sedentary reminder,music player,alarm clock, watch,camera,remote camera,bluetooth sms/message notifier,message reminder,call reminder,answer call,dial call,nfc for quick pairing. Sync function: whats app, twitter,facebook;time,schedule,read message or news;entertainment: ,camera.Bluetooth connection support ninety nine% of mobile phone market samsung,htc,nokia,motorola, most have bluetooth function and mobile phone can use. Shut down automatically, the charge time need 1-2 hours, this product only work in 2g sim and without I pin security it work.Once the sim is inserted in the sim slot it needs to be activated by the service provider.