A free program for Android, by Insurance Viral Dev.
This app offers the latest collection of wallpapers, all of which are inspired by the game, and you can choose to have them as your home screen or lock screen background.
Once you open the app, you will be able to browse through a list of popular wallpapers. You can also browse through the latest additions, and you can even search through the entire collection to find the one that you want.
After finding the desired image, you can just tap and tap again on the check mark to install it as a background image. You will not have to leave the app to do that.