I played arround with the CameraEX class and after some crash the camera wasn't available anymore. Only a restart fixed it (I think it's not freed and so still in use). There were no active apps running or in the background. Is there a way to do some sort of "force free" to get it back without a restart of the device?
It is worth monitoring the unfiltered logs. Might provide more information about the crash.
It is the OS responsibility to release all resources when the process is killed. If the OS didn't release it then is most cases there is nothing that you can do about it.