For lots of situations, you may want to just use your controller rather than connecting a mouse or touching the screen. Now, you can move the mouse and interact with the desktop and game via the controller plugged into your client computer or phone.
To enable controller-driven mode, use the hotkey on the controller.
To enable controller mode, press SELECT + UP on the D-PAD
Once you press that, the controller begins to act like your mouse, and the controller is mapped like this: