Wallcat - Enjoy a new, beautiful wallpaper, every day.
Unsplash Wallpapers for Mac (Official) - Curated, HD desktop background photos from Unsplash.
Splashify - Beautiful desktop wallpapers for Mac and Windows
Wallpaper Wizard - Wow-worthy backgrounds for Mac
Irvue - (previously Unsplash Wallpaper) Gorgeous wallpapers on your Mac.
5K macOS Wallpapers - Every default macOS wallpaper – in glorious 5K resolution!