Monetizable Android Action Game

I’m a student with a clear goal: launch an engaging action-style game on Android that can start earning right away. I have the core concept sketched, but I need a seasoned mobile-game developer who can turn that idea into a polished, store-ready APK... (Budget: $250 - $750 USD, Jobs: Android, Game Design, iPhone, Mobile App Development, Prototyping, Unity, Unity 3D, Unreal Engine)