John's Background Switcher - Switch backgrounds to trending imgur, reddit, tumblr threads
Wallpaper Engine - Wallpaper Engine enables you to use live wallpapers on your Windows desktop.
Wallcat - Enjoy a new, beautiful wallpaper, every day.
Lively Wallpaper - What is it? Lively is a Free and Open-Source Software (FOSS) for animated desktop wallpapers.
Splashy - Breathtaking, auto changing wallpaper app for macOS, Windows, Linux, iOS & Android
ScreenPlay - Open-source and cross-platform Wallpaper, Widgets and AppDrawer app.