Perhaps the very best wallpaper app is Google Search. You look for what you want. The upside is that you could get creative with searches and discover virtually anything you want. The downside is that you need to get creative to locate good stuff in any respect.
There is lots of fluff in terms of wallpapers and barechested backgrounds, and Google Search does not clear out something. In any case, we recommend you either begin with Google Search or end with it if none of those other wallpaper apps do the trick.