Autosplit

This is one of those ridiculous concepts that shouldn't work but it does. One of the big reasons is its attitude toward in-game purchases. This is a true free-to-play game; you can play as long as you want without paying anything (though you do have to endure frequent short ad pop-ups.)

The game's generous reward system gives players -- especially good ones -- an easy way to collect all the cool extras without breaking the bank. Better still, it makes spending money seem fun rather than an obligation. Aside from its deft handling of money issues, Autosplit gets the thumbs up for its addictive absurdity. Changing up the character/vehicle combos keeps things fresh, and you won't believe how satisfying it is keeping a zombie upright atop two lumbering pigs. Obstacles become more and more random as you progress, which adds to the hilarity; just when you think you've got avoiding the sea monster and selfie-girl down, Thor, the god of thunder appears and knocks you into the street. Though there are some things in questionable taste (like the collectible character sitting on a toilet) and the ad pop-ups are annoying, this is a deceptively simple app that's good for hours of fun.