There are lots of cases, especially in say marketing images, where the entire screenshot is not the content. You may want to highlight a specific bit of UI whil

There are lots of cases, especially in say marketing images, where the entire screenshot is not the content. You may want to highlight a specific bit of UI while still keeping the general background context instead of cropping into a small image. This lets you click a portion of the screenshot to bring into focus. At the end of the day it's a fun toy web app, but I don't think the general concept is useless.