I am running this viewer with one of my maps and it runs very well except for the layer browser. The issue is with expanding a layer which contains sublayers. When I click on such a layer it switches to the loading animation and does not advance further. The list of sublayers does not expand out like on your demo site. I've been looking at the source and am pretty stumped about why this is happening. Does anyone have any ideas what is going wrong?
1. Embrace the use of responsive design. I think it's possible to achieve something that resembles the AJAX viewer with the classic 3 column layout on a desktop/tablet that nicely collapses down to just the viewer on a phone, with the legend and task pane columns hidden but exposing toggle buttons on the edge that you can use to "pull" that panel in and to "push" it back out. Of course using responsive design brings the IE question into play, but this is a mobile viewer right? Who'd use a mobile viewer in IE anyway? :)
2. Have a PHP backend for the viewer as well. Not because I like PHP, but because PHP is required for both Windows and Linux versions of MapGuide, having a PHP backend means you can make this viewer available on both Windows and Linux versions of MapGuide.