During the launch of iOS 7, Apple touted MFi Game Controller Support as one of the many new features coming to iOS 7.
Touch Arcade has posted photos of an Apple developer guide illustrating the style of controller interested Third-party should be made via the MFi program. This is the program in which Apple issue licenses to other manufacturers to build accessories for their products.
The illustrations show two controller design: The first design appears to an add-on to the iPhone with left and right shoulder bumpers, a D-pad, four action keys (Y,B,A,X) and a Home button. The second design depicts a stand alone game controller with similar features to the first except fro the addition of two Joysticks.
A patent granted to Apple last year showed that the Company was interested in allowing gamers to pair a NFC enabled game controller with Apple products using the same technology.