[FREE] Chosen - challenges app

Hi,
Here's an app for challenges between friends and others.
It's still a work in progress, and we're gonna add some stuff soon, but I'd love to get some feedback on the look and feel...
As I'm new to this forum, apparently I can't give the link to Google Play, but here's the screenshot (it's easy to find - search "chosen"):

Would really appreciate any inputs, good or bad!
Thanks,
Mike