Setting a wallpaper requires you to go to gallery and fidget a bit.To solve this problem there is a new android app called AutoWall (beta) which lets you directly set a wallpaper after you click a selfie with custom camera or any picture with back camera.
Activate - yes or no
Ask before set - yes (pop up will appear) or no (direct pic/selfie to wallpaper)
Crop before set - yes or no
The best thing about AutoWall is that you don't have to go inside the gallery or use any camera in the app to set a picture as wallpaper.
Crop mode is on
If crop is on you can crop the selfie,otherwise it directly sets as wallpaper.
No need to go into the app and use camera from the app.Just use normal android custom camera.
If both crop and ask before set is off then the picture directly sets as wallpaper.There is no pop-up/notification or cropping screen.
It is easy to use.Try it once :)