There is no bitcoin as the reward? If so, I think it should be moved to Service Announcement (Altcoins).
Anyway, it is great that this app is compatible with almost all android version.
Waiting for the bitcoin version.
You can convert BELA to Bitcoin in Poloniex. He include it in the first post. Btw, have you tried the app? I have troubles accessing it so I was waiting for someone to confirm that they can play the game to confirm if it is my phone or the app just doesn't work.