A while back, we reported about the Pixel launcher along with a method for installing it. In order to be able to use the wallpaper choose, we were also required to install a second APK which would bring the wallpaper chooser's own functions. Today, you can download Google's own "Wallpapers" app which brings the same functionality to any other Android smartphone. You can choose from different categories like: Earth, Landscapes, Cityscapes, Life, and Textures. You can find a large variety of wallpapers on any of these categories, and you can also set a category to display a new wallpaper...
Source: http://www.gsmarena.com/googles_wallpapers_app_brings_the_pixel_wallpaper_chooser_to_all_android_phones-news-21182.php