QuickBlock is a free game that helps you train your reflex by moving green block around the screen and trying to avoid contact with orange blocks. Additionaly grab small blue blocks to incerase your score!

Sidenote: At the point of posting this program has been marked as beeing freely available without costs. As this program is hosted with the AppStore the status might change. Authors like to publish their programs for free for promotion purpose and then make it commercial. Also it could happen that the author decides to take the program down.

http://appshopper.com/games/quickblock