Given how clever the Scribblenauts games have been, it's hard not to pay attention to what developer 5th Cell has in the works. Their next game, Run Roo Run, isn't quite the imaginative "do whatever" kind of game Scribblenauts was.

Described as a "micro-platformer," Run Roo Run is similar to other "auto-run" games, like Canabalt. However, instead of running through a randomly generated stage for as long as possible, you will be going through one of the 420 pre-designed levels.

Run Roo Run will offer both "normal" and "extreme" levels, in an effort to appease both casual and hardcore players. "Players unlock the extreme levels of each chapter after beating the normal ones," creative director Jeremiah Slaczka explained to Joystiq. "But you can completely bypass the extreme levels and just focus on the normal levels if you want. I wanted to make sure both casual players and core gamers had content to enjoy."

And, as with many other mobile games, Roo will be constantly updated with new content. 5th Cell is promising to add 10 new levels for free on a weekly basis, via a delivery method that "won't require a product update."

Run Roo Run will be available on the App Store for iPhone, iPad, and iPod Touch this Thursday. Visit Joystiq for more screenshots.