After a brief Xperia device exclusive, Call of Duty Black Ops Zombies is now available for most Android devices. The game itself is another Zombie shoot ’em up, which frankly, is getting a little old. Glu mobile has also decided to drive users bonkers by charging $6.99 for the game as well as including in-app purchases. This model is a far cry from what MadFingers Games is doing with their free Zombie hit Dead Trigger. By comparison, Dead Trigger (which dropped its price to free) has amassed almost 5 million downloads in two months while COD: Zombies with their $6.99 price tag has only managed a couple thousand downloads in the month that it has been available.