[afloatboat]

I occassionally use PhotoSwipe when I need an image viewer (http://photoswipe.com/documentation/getting-started.html). Bit of a pain to implement, but I really like the way it works both on desktop and mobile and the fact that it has linkable URLs.

For all the over the top options that ViewerJS seems to have, I find it strange that a simple 'click background to close' option is missing.