1. Charging your Android smartphone with another smartphone using USB OTG
This could be one of the most loved uses for the Smartphone users. The only thing you have to do is connect the two smartphones and the phone that acts as the USB host will start charging the other device. This might help you a lot in the case of emergency. With this technique, you can also charge non-android phones by applying the same procedure. Just remember that for this trick to work, the host device needs to have a higher battery capacity compared to the smartphone you wish to charge.
2. Connecting it as a Game Controller for playing games on your Android smartphone
You will never believe this! With the help of OTG cable; you can easily connect a Game Controller. Though the Game Controller may not be as useful for playing games on your smartphone, but still you can get the best use out it instead of using your smartphone’s touch screen to control the game. Also more and more Android games come support the use of an external gamepad making this trick an absolute must have.