Which geometric, rounded, Bauhaus style fonts are similar to this sans-serif 'Abeat by Kai'?

I'm building an iOS 8 app and would really like to use the font A beat by Kai created by Kai Buskirk.

Font sample:

This font is free for personal use but not for commercial use.

I'm wondering how I can buy a license for commercial use on an App in the App Store, or if you can recommend similar fonts that I can use for my apps?