Call of Duty: Zombies touching iPhone

Call of Duty: World at War has already proven that it has legs well beyond its initial launch. With more than 11 million units sold since the well-regarded World War II shooter launched in November 2008, Activision said in July that the game's first two map packs had combined to sell some 4 million units. That figure, of course, doesn't even include Map Pack 3, which hit the Xbox 360 and PlayStation 3's online services in August.

With Call of Duty: Modern Warfare 2 and its record-setting launch still a headline fixture, Activision today announced one more World at War extension, this time for Apple's iPhone and iPod Touch. The publisher said today that Call of Duty: World at War: Zombies can be downloaded through Apple's iTunes for $9.99.

As its title suggests, the touch-screen-enabled shooter continues the zombie theme established in the first three World at War map packs. Call of Duty: World at War: Zombies accommodates solo play as well as co-op for up to four via Wi-Fi connection as gamers are charged with fending off waves of the undead hordes.