I don't believe there's a command to "close apps"... but I think what you're really after is to get back to the map. Perhaps something like "show map" or "show navigation"... although those are totally wild guesses.
It used to be that windows had an explicit close.botton (an X in the corner), but at some point that switching to just swiping down. I don't find that I really need to look at the screen to close a window. If I do, then it's a very quick glance and I'm not even aware of it, or it just requires a tiny bit of my peripheral vision.
If you're a new owner, then I think in time this will become a non-issue for you. Good luck!