id Software just released the source codes for iOS titles Wolfenstein 3D Platinum and Doom Classic in the newest batch of updates (2.1). If you're into it, grab the source code for Wolfenstein 3D Platinum right here, the source code for Doom Classic right here, and the trailer for the 2011 sci-fi thriller starring Jake Gyllenhaal, Source Code, here.

If you don't care how your games work, so long as they just work, update 2.1 features a revised user interface, remastered HUD, improved framerate for Wolfenstein and the removal of multilayer, which id will integrate later in a "more robust fashion."