XScreenSaver is a large collection of historic and educational graphics demos.
These all work as both Daydreams and Live Wallpapers.
XScreenSaver is the standard screen saver collection shipped on most Linux and Unix systems. I released the first version in 1992. In 2006, I ported it to MacOS, and in 2012 I ported it to iOS. This is the Android port, 2016.