Pi - The Game, developed by Oval Software Oy, is a free game app that aims to help improve your Pi memorization skills. It is currently the #1 Pi app on the App Store.

The app offers several features to help you memorize Pi, such as the ability to write your own Piem, view statistics on your performance, and sound effects to aid memorization. It also has a reverse button order to make it more challenging and includes full Game Center integration, allowing you to challenge your friends to beat your high score.

Overall, Pi - The Game is a great way to improve your Pi memorization skills while having fun. The app is easy to use and provides helpful features to aid in memorization.