PopCap Games, Inc. has Plants vs. Zombies (iTunes Link) in the iTunes App Store for 99-cents (4.99-4 instant savings) for a limited time.

PopCap Games, Inc. also has Plants vs. Zombies HD on sale for $4.99 (9.99 – 5 instant savings) for a limited time. Both deals expires October 31, 2010.

A mob of fun-loving zombies is about to invade your home. Use your arsenal of 49 zombie-zapping plants — peashooters, wall-nuts, cherry bombs and more — to mulchify 26 types of zombies before they break down your door.

id Software has Doom Classic and Doom Resurrection (iTunes Link) in the iTunes App Store for $1.99 each (regularly $6.99) for a limited time.

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.

Then immerse yourself in the first person on rails experience that takes your iPhone or iPod Touch beyond previously imagined limits. Introducing DOOM Resurrection, a brand new, technologically advanced, heart-pounding chapter in the legendary DOOM Saga!

Scientists on a remote research facility on Mars have lost control of their experiment and all Hell has broken loose. As the last surviving Marine in your unit, you must defeat Hell’s minions and unravel the mystery of what has happened on Mars. Earth’s future depends on you!

Courage alone will not be enough to stand up to the evil that awaits you. Utilize a devastating arsenal of weapons, helpful NPC’s and your environment to succeed. With an assault rifle, shotgun, a vicious chainsaw, and more, you will even the odds in a raging battle against unnatural beasts hell-bent on flaying your flesh and damning your soul.

With its revolutionary control scheme, breathtaking visuals, and intense story, DOOM Resurrection is sure to provide the adrenaline rush you’ve been craving.

Gameloft has James Cameron’s Avatar (iTunes Link) in the iTunes App Store for 99-cents (regularly $6.99) for a limited time.

Go deeper into the spectacular world of James Cameron’s Avatar™ and embark on a fantastic journey of redemption and discovery two decades prior to the film events. As the first experimental avatar, experience the amazing powers your new body bestows. Will you use those powers to save the Na’vi, or will you work with the humans to destroy their world?

SQUARE ENIX Co., LTD. has Final Fantasy or Final Fantasy II (iTunes Link) in the iTunes App Store for $3.99 (regularly $6.99) for a limited time.

Initially released in Japan in 1987, the original FINAL FANTASY amazed audiences with its rich story and stunning graphics.

Players guide the Warriors of Light as they set out on a quest to restore the crystals to their former luster. Its side view battles, choice and promotion of character classes, and sprawling world explored with fantastic vehicles quickly became standards of the series. This game set the stage for all FINAL FANTASY games to come.

This edition also contains the bonus dungeons added to later editions of the game–the Soul of Chaos and the Labyrinth of Time.