Dear Sebastian,
You have created a good app but a few flaws have prevented it from being 5 star.
1- completely disabling the toolbar (camera, settings icon) to access the settings we could just tap an invisible settings button in the same location.
2- the application needs to force mute on start. Id hate to forget or mistakenly reactivate the noise switch.
3- as mentioned before the camera area is much smaller on the iPhone 4 please make the camera viewing area full sized.
Please updated your awesome app XD
Da7dal about Cam-u-flage