iPad Game for Cats is a free download through the App Store, but the "free" part is very misleading. Even though the game's website and the App Store page say that it's gratis, you actually can't get anywhere unless you make a 99-cent, in-app purchase.
Edit (12 AM 12/21): The developer got in touch with me regarding this via Twitter and has since updated the app description to clarify that the mouse game is an in-app purchase. Thank you so much!
But, you do get a little time with the game, and there's only one way to test it and that's with a cat ... or in my case, three cats.