App freezing after voice call

I've made an applica开发者_开发百科tion that is pretty simple, it just lets the user capture a number and then saves it in a SQLite DB.

Sometimes, not very common thing, when the user is entering the number to save in my app and he receives a call, answers the call, and then finishes it, the application is frozen after the call, can't do anything on it, not even return to the previous screen.

Does anybody have a clue on what can this be?

The code in this application is so simple =/, I have no idea what could it be.

Thanks in advance!!

How is it frozen? Have you attached the debugger and looked at your processes/threads to see what they are doing?

Could it be a painting issue rather than true freezing?

Need more information.