Sigil - Sigil is a multi-platform WYSIWYG ebook editor. It is designed to edit books in ePub format.
Variety Wallpaper Changer - Variety is a wallpaper changer for Ubuntu which is featureful, yet slim and very easy to use.
Jutoh - Epub editor, convertor and creator software for Mac and PC.
Splashy - Breathtaking, auto changing wallpaper app for macOS, Windows, Linux, iOS & Android
WLPPR - Beautiful mobile wallpapers made from satellite imagery
Wallcat - Enjoy a new, beautiful wallpaper, every day.