This recipe sets your Android Wallpaper to the Bing Image of the Day and avoids duplicates, because it only uses the pictures of one country (default US).
If
New feed item matches
This Trigger fires every time a new item in the feed you specify contains a particular keyword or simple phrase.
Then
Update device wallpaper
This Action will update the wallpaper on your Android device from the image URL you specify.
Explore more great ways to automate Android Device and RSS Feed