Pinch In/Out in mobile

Hi, I've succesfuly implemented and customized viewer.js in a responsive template, adding Draggable option. I can swipe between the pages, but I would like to zoom in / out in pinch event of mobile. I ask you if exists a plugin which solve this. The precarious solution I found is catching this event and throw zoom method, but I would like to get a better solution. Alternatively, I could develop and publish it but I would need your help.

Thanks!

Begin by reviewing viewer.js's Draggable option and existing zoom method, then inspect how mobile touch and pinch events are handled. Done means an agreed plugin or implementation supports pinch-to-zoom without breaking page swiping; the issue names no target file or test, so validation criteria need to be established first.

Written by the indexing model from the issue text.