Have you been able to address your need? What kind of map data do you need devices to have? If simple points, lines and shapes with minimal styling will work, then I agree that select_one_from_file map.geojson is the way to go. You can find documentation for it here.
If you need offline maps with more complex styling, it would be helpful to know more about your need. What's your ideal format to use? How big are the files?
We are actively working on a way to load local mbtiles in an easier way. Those mbtiles could be hosted on a server but would not be on the Central form server.