Scrie o aplicație pentru Android

I have an application for android, what have a bug. The application working with a error. How it works the app: - answer the call with double click with a finger on screen, - reject the call with a click with two fingers on screen, - and silent ringing with a click with a finger on screen, The error: after close the application, the phone not more ringing at maxim volume, the gps voice is too low, or any other application have very low sound. For use the phone normally, it must to restart the phone. That's not good. Can you fix it?