I was thinking about how annoying carrying out many simple tasks on the iPhone are. For example, I was playing a game the other day and wanted to increase the brightness, which meant quitting the game, tapping my way into Brightness, adjusting, then restarting my game. Annoying! But if the phone was multi-touch rather than just 'dual-touch', there could be the option to, say, slide three fingers up and down the screen the adjust the brightness. Double-tap with three fingers to turn wifi on and off etc. etc.