Doom Classic is an iPhone/iPod touch port of Ultimate Doom developed by id Software. According to the development notes released by id, the port is based on PrBoom and uses OpenGL rendering and controls similar to the Wolfenstein 3D classic title. Since it is derived from a GPL codebase, the source code was made available.
It was made available in the iPhone App Store on October 31, 2009.
All of the classic monsters appear in game, along with all the classic weapons.