Planet Explorer - Interactive global satellite images
Planets Facts Site - A powerful website that details information about planets.
Wallcat - Enjoy a new, beautiful wallpaper, every day.
Splashy - Breathtaking, auto changing wallpaper app for macOS, Windows, Linux, iOS & Android
Splashify - Beautiful desktop wallpapers for Mac and Windows
Irvue - (previously Unsplash Wallpaper) Gorgeous wallpapers on your Mac.