Press and hold the PS and Share buttons on your DualShock 4 until it enters pairing mode (shown by the flashing white light bar on the back of the controller). Open your Android phone's Settings app.
Many players would prefer to have fun with GTA 5 using a controller than with a keyboard. If you have a spare PS4 controller lying around and want to know how to use it to play GTA 5 on Epic Games, ...