Bungie's classic first person shooter Marathon [iTunes] is now on the App Store for the iPad. The free download offers 27 levels divided into 6 chapters. The interface has been modified to accommodate touch screen interaction of the iPad.
Marathon was first released by Bungie Software for the Macintosh in 1994. It was a Mac exclusive launch and was released shortly after Doom was first released for the PC. Bungie later went on to be acquired by Microsoft and released the popular Halo game series for the Xbox.
The iPad version of the game started off as a personal project by iOS developer Daniel Blezek but was later officially sanctioned by Bungie. The iPad version of the game is free to download, but an in game store offers two in-app purchase options. The first is called "HD Mode" for $3.99 and features new high resolution textures to replace the walls, floors and liquids. The second is Master Chief Mode for $0.99 which offers the ability to start on any level, infinite ammo, all weapons, instant recharge, invulnerability and instant save.