ESP-12 (ESP8266 ) is an ultra-low power UART-WiFi module. It has excellent dimensions and ULP technology compared to other similar modules. The module is special design for mobile devices and Internet of Things . Once firmware is upgraded to the appropriate version, a compatible Android device can run the IOT.APK to do the following:control the PWM, I/O pin, or Serial communication. For example,you can use this module transmit date with it serial port.It is easy to communication with other device.