From the Unity blog:

Like most mobile games developers, we’ve been closely following what important additions and changes the recently released iOS 7 update has made. One of the biggest and most exciting of Apple’s initiatives is the standardization of game controllers for iOS-based platforms. So we’re happy to tell you that, in addition to several important bug fixes for Xcode 5 / iOS 7 (Build&Run, WebCamTexture and status bar), Apple Controller support is included with 4.2.2! This blog post aims to answer most common questions this addition will raise and serve as a short tutorial on how to add support for iOS Game Controllers to your game.

With iOS 7 now approaching its first full month of public availability, game companies are starting to show their support for iOS 7’s new Game Controller APIs. Besides Unity, ClamCase announced their first official controller and leaked photos showed one from Logitech.

With an Apple media event reportedly scheduled for October 22, I have to wonder if further game controller announcements will be held back until that date. Apple likes to invite developers on stage, and third-party controllers for iOS 7 and OS X Mavericks would certainly make for an interesting demo, perhaps showing compatibility for both iOS devices (new iPads are rumored to be announced at the event) and Macs.

As I argued in June, there is great potential for game controllers and AirPlay, and I’m curious to see if and how Apple will start promoting this feature more aggressively.