Sometimes a sequel to a sub-par game is so close to the original, you wonder why the game developers bothered. Other times, the sequel is so far removed from what made the first one popular that no one cares. Then there are games like G5 Entertainment's Youda Survivor 2 HD (Free, or $6.99 In-app purchase for full game). While mechanically it doesn’t seem much different than its predecessor, it’s so easy to get into and so hard to put down that you won’t care. I’m not sure what makes the style of game play so catchy, but whatever it is, the developers behind the Youda Survivor series have pretty much perfected it.