This app hides a portion of display or rather locks it and makes itself unable to move, close, minimize etc. The app can set colour or image as its background as per user choice and a key for user to lock and unlock its position.
However the app process can be highjacked by apps that are "always on top" like chrome full screen and the process of the app can be tempered with through advance windows controls or maximized app movement. So it is a good tool but not a guaranteed way to protect screen but still for basic use will work nicely.
