A free app for Android, by mortisApps.

ScreenGuard is an easy-to-use screen filter app that makes it easier to write, read, and surf the web privately. You can easily switch between different filters to get the best privacy and readability.

There are a variety of different filters you can apply to your screen. These include simple black and white filters as well as more advanced ones that allow you to select from a variety of colors.

When you're finished, simply save your settings as a profile, so you can easily switch between them to get the best privacy and readability.

ScreenGuard protects your privacy by applying a screen filter that makes it harder to read your screen, great for when you're reading e-mail, writing an SMS, or using the browser.