The biggest challenge with mobile game design is not so much the precision of controls, it's the premium on screen real estate. You have to put all the informa

The biggest challenge with mobile game design is not so much the precision of controls, it's the premium on screen real estate. You have to put all the information of your game on the same layer as the controls- meaning your number one concern will be optimizing your interface and controlling the flow of information. It also means that the games you'll be making should be unique to touchscreen- games ported from other platforms are almost always inferior, in part because their design is optimized for a different platform.