Spawn Glow is designed to help you create colorful abstract wallpapers. It features groups of brightly colored lines, flying around the screen based on your gestures. You can make the lines explode into a flurry of sub-lines with a simple tap, and change the colors of your lines to your liking.
On the other hand, Art of Glow is designed to create actual drawings, as the app features series of colored shapes that precisely follow your gestures. You can pick the color you want, as well as the shape that will be used for your lines (starts, circles, hearts…).
Both apps are simple to use, and help you create fun wallpapers in no time. Spawn Glow is free, and makes impressive abstract wallpapers, but note that its ads are annoying. On the other hand, Art of Glow is not free, but it produces the best results if you want to put together more realistic wallpapers.