Freedoom is an innovative project designed for iPhone users, providing an open content alternative for the classic Doom engine. This action game includes three IWAD files: Freedoom: Phase 1, Freedoom: Phase 2, and FreeDM, which is tailored for deathmatch gameplay. The game allows players to immerse themselves in classic single-player campaigns or engage in competitive multiplayer matches with a variety of levels.

The Freedoom project complements the original open-source code of the Doom engine, released in 1997, under the GNU GPL license. With content licensed under the permissive 3-clause BSD license, Freedoom supports custom levels and modifications, enabling users to enhance their gaming experience with additional PWAD files. This flexibility makes Freedoom an appealing choice for both nostalgic players and new users exploring the world of Doom.