If you want your Arduino to transmit data with other device or control PWM, I/O pin, serial communication of the Arduino by PC or phone client. Trust me, you definitely don't want to miss it- our Elecrow ESPduino! It will help you a lot and save your time on the connection. It combines a Arduino UNO with a serial WiFi and can be apply on lots of project of IOT, such as Smart Home, Smart robot, Security system. The same size with more powerful function, this two in one board will give you surprise!