This extension rocks! Is it possible to test pages in mobile view?
Topic on Help talk:Extension:TemplateSandbox
The extension doesn't do anything to stop itself from working on mobile, but at the same time I don't think anyone has done any work to integrate it with all the special things mobile does. So there's no UI for it in mobile's editor, but you could potentially use the API action=parse endpoint to build a gadget or something (assuming mobile didn't make its own special replacement for that too).