In Anandtech’s review of the new iPad, they reveal knowledge of an internal Apple project that involves a physical controller for iOS gaming:
Although many casual Android/iOS games do just fine with touch, some are certainly better suited for some sort of a controller. While controller support in Android in its infancy at best, it’s more than iOS currently offers. I know of an internal Apple project to bring a physical controller to market, but whether or not it will ever see the light of day remains to be seen. As smartphones and tablets come close to equalling the performance of current game consoles, I feel like the controller problem must be addressed.
Certainly there are games that are better off with physical buttons. Touchscreen gaming doesn’t work for all games. We’ve seen physical controller add ons such the iCade Mobile and the iCade 8-Bitty. Would an Apple version of a physical controller add-on to your iPhone be something you’d want to have?