If you're a mapper and want your release to have a place in the app, simply make a post about it on our forums in this section, include a few screenshots and a descriptive outline of the map (a video would be great) and we'll review the post before adding in the map. The only real prerequisite is that you have put some effort into making the map; this doesn't mean it has to be extremely detailed, large or perfect in any way. In fact, we'll happily accept new mappers' first releases, as long as they have put a little thought and effort into building something more than a simple box with no buyable areas and zero uniqueness
Otherwise, if you're just a player and are looking for some fun & diverse maps, not only from UGX but from the wider community, start checking the app every now and again as we'll be adding quite a few maps in the weeks to come!
The UGX Map & Mod Manager app can be downloaded here:
ugx-mods.com