DOOM Classic 1

butterscotch says:

A gadget is not a gadget until it gets a DOOM port...

the author of this app says:

Critical Acclaim for DOOM Classic:

"Best of 2009" Top 10 Game, iTunes Rewind

For shooter alumni, this version of DOOM on the iPhone is a flawless reminder of why it's considered among the best of all time. Slide To Play

another stellar effort in retro FPS gaming from id. TouchGen.com

Welcome to Hell! Prepare to relive the First Person Shooter that defined a generation with the legendary original DOOM - now on the iPhone. As a space marine stationed on the planet Mars, you are all that stands between the armies of Hell and their invasion of planet Earth!

DOOM Classic includes the original three episodes as well as Episode Four, Thy Flesh Consumed, spread across 36 levels of non-stop carnage and action.

Choose from customizable control schemes, all designed by id Software co-founder and industry legend, John Carmack. Wield unforgettable weapons like the Chainsaw and the BFG 9000 while fighting through notorious monsters like the Imp, Cacodemon, and Hell Knight!

In DOOM Classic, multiplayer action is reborn! With a wireless connection, battle up to four players in Deathmatch mode, or work together cooperatively and fight back against the demons of Hell.

Features:
Play the legendary first person shooter, DOOM, with an iPhone or iPod Touch.
Fight through 36 missions in four action-packed episodes: Knee-Deep in the Dead, Shores of Hell, Inferno, and Thy Flesh Consumed
Experience DOOM multiplayer on your mobile device, including Deathmatch and Cooperative play for up to four players via wireless internet.
Choose from three different control types and customize the interface to suit your style
Explore the depths of Mars while utilizing the topdown map to help you explore and save your game on the fly.
Listen to the original soundtrack or disable it and use your own iPod music