Insert your phone SIM Card in the smart watch and this watch will become a smart watch phone. You can make calls, receive calls and view messages that are sent after the SIM card is installed in the smart watch. Dedicated SIM Slot, With a dedicated SIM slot, receive calls, text and read or send emails with the Captcha smart Watch. Sync all your mobile data, Now sync all your contacts and media on the Captcha Smart Watch. Now make Calls and messages, Sync your mobile phone with the smart watch using Bluetooth. Once your watch is connected to the phone you will be able to access your phone book and make calls.Y1 Smart Watch support Nano SIM Card and TF Card smartwatch on sale Y1 Smart Watch Features: CPU: MTK6261D Screen: Touch Screen ,1.54 inches IPS ,240*240 pixel Battery: 280mAh Moto: 0827 TF Card : MAX support 32GB SIM Card: Support Nano SIM G Sensor: Yes GSM: GSM850/900/1800/1900MHz Bluetooth: 3.0LE Functions: Calendar,clock,tape recorder,calculator,settings, file manager, pedometer,sleep monitoring.