Mouse Control
If your device supports mouse control you can use this to steer your racer and use its buttons and scroll wheel for other control. Mouse control is an effective way to steer your racer, but there are some issues you should be aware of.
Android
Most android devices will support a mouse, but they offer limited support. Some of the mouse buttons can not be overridden. Certain buttons on your mouse will behave as Home buttons forcing the game to pause and your device to navigate to your home screen, unfortunately this can not be overridden on most devices. Most devices will also always show the mouse pointer on the screen during game play, which is not ideal.
Apple iOS
Apple iOS touch devices, such as iPhone and iPads do not support mouse control.
Mouse Settings
Select mouse control by selecting the picture of the moving mouse at the top of the Options → Controls screen, next to the Steering Control heading.
More
Hit the More button to access the mouse button assignments.
The settings page should be fairly self explanatory. If you connect a keyboard you can also use keyboard keys to activate game functions. Press a button to highlight an action, such as Brake. Once highlighted you can press a key or mouse button to assign it to that action.