Looking for a free app that delivers thousands of high quality wallpapers? Wallbase HD Wallpapers has you covered. The app is a client that aggregates images from the online wallpaper site wallbase.cc (which, by the way, is definitely worth checking out). Wallbase itself is a 4chan.org wallpaper scraper, so some of the images may be mature.

You can easily browse by most popular, or search through thousands of different tags and categories. The app ran extremely quickly on my Android, and delivered thousands of awesome images.