Android: How to safely unbind a service

Here you can find a nice explanation and source codes how to work with bound services. In your case you should override methods (onServiceConnected and onServiceDisconnected) of ServiceConnection object. Then you can just check mBound variable in your code.

Try this:

boolean isBound = false;
...
isBound = getApplicationContext().bindService( new Intent(getApplicationContext(), ServiceUI.class), serviceConnection, Context.BIND_AUTO_CREATE );
...
if (isBound)
    getApplicationContext().unbindService(serviceConnection);

Note:

You should use same context for binding a service and unbinding a service. If you are binding Service with getApplicationContext() so you should also use getApplicationContext.unbindService(..)