The latest version of iMAME4All, a jailbreak app that lets you play retro arcade games on your iOS device, added support for the iCade desktop arcade cabinet for the iPad. It lets you play any MAME (Multiple Arcade Machine Emulator) compatible ROM on your iCade and opens it up to a variety of previously unsupported games.
If you don't want to go the jailbreak route, iCade recently released a SDK so any iOS game developer can officially support the gaming cabinet. When it launched earlier this year, the iCade only supported the Atari's Greatest Hits app which has a collection of retro Atari 2600 games. With an SDK and iMAME4All support, the iCade is now a lot more interesting to hard-core gamers with an iPad.
Apple iPad Air 2