... Right, very interesting.
... Into android, an app. exits too :"after focus" (DSLR like)http://calcunico.blogspot.fr/2013/04/af ... -your.html
"...After your shot is taken the app can let you select which areas of your photo to blur and to what degree by drawing lines with your finger to indicate the point of focus. There are also several other image after effects."
... But I do not know if a pluggin can do that via XnView ?