Usually when we think of pairing a wireless controller to an Android device, it is a Playstation 3 or Wii controller. While there is certainly nothing wrong with this, there are those who simply prefer the Xbox 360 controller. While the wired variant has worked on Android natively for a while, there is now a way to get a Wireless Xbox 360 Controller working on a Nexus 7.

XDA Senior Member sleeplessninja has figured out how to get a wireless Xbox 360 controller working on the Nexus 7. Usually, for Xbox 360 controllers, you need a wired controller and a USB OTG cable. There is already a way to get the controller working on the Nexus 7 using a Xbox 360 Wireless Controller Dongle, but there are a lot of games that still can't register the controller properly.

This issue has been fixed. As sleeplessninja explains:

So when i searched through the /system/usr/keylayout/ I saw there was a profile for the xbox 360 wired controller so I thought why not copy the profile and name it a wireless xbox controller. This idea worked. You name keylayouts by Vendor ID and Product ID which I also was able to get from the logcat. What is nice about this is I think we can use this to solve issues with other controllers as well, but I don't know of any that are also having problems.

So once the simple modification has been made, you can use a wireless Xbox 360 controller to its fullest potential. And, as stated, this method could be used to fix issues with other controllers. To learn more, head to the original thread.