Simple jQuery script

I have an app which displays content in a Web browser. Recently we have transitioned from using markdown (in this case, [login to view URL]) to render our script to using straight HTML. We use swipebox ([login to view URL]) to display images as well as a default image when network connectivity is not available. We modified our [login to view URL] file to render img tags appropriately - that is, it must be of the following format: <a href='(image URL)' class="swipebox"><img class="backup_picture" src="(image URL)"/></a> That was ok previously but now I need to do all this on the device, using javascript, from just <img src="(image URL)"> So - $20 to the solution that works, including where to put the code. The device comes with jQuery 2.2.3 Thanks