Presumably due to the forthcoming movie, Teenage Mutant Ninja Turtles: Rooftop Run is free on the App Store at the moment.
The game allows you to control your favorite turtle as he runs, jumps, fights, and drives his way through New York's endless landscape.
We weren't too keen on Teenage Mutant Ninja Turtles: Rooftop Run when it first came out, mostly because there was a ton of grinding to it. However, as it's gone free for a limited time this might be just the right time for you to see if you agree with us.
We're not sure how long it's on sale for, so we'd suggest grabbing it as soon as possible.