The Bing search homepage has a beautiful photo that is updated once every day. You can set this photo automatically as the wallpaper of your Android device using the Muzei app.
Install the Muzei Live Wallpaper app. You can see that it can set the wallpaper from many sources.
To add the Bing photo as a source to Muzei, install the Muzei Bing Addon app.
Open Muzei and choose the source as Bing. Its daily photo will be updated automatically as your wallpaper every day.
Tried with: Muzei 1.0.1, Muzei Plugin for Bing 1.3, Android 4.4.3 and Moto G