It's difficult to get an app accepted by Google. The last time we tried they couldn't get their heads around the idea of a faucet and confused it with Proof of Work mining. We'll try again and hope that whoever gets to check it actually knows something about bitcoin next time.
I think it can be difficult to be accepted on Google Play. Freebitco.in is considered as gambling website and Google Play doesn't allow such apps. It's main reason why it will be very difficult to upload Freebitco.in app to Google Play store.
Many gambling or sports betting websites have their own apps, but it can't be found on Google Play, you can only download .apk file from gambling website what is probably not convenient for most of users.