Well, it kind of works essentially, but some features which I absolutely need are missing, for example switching keyboard layouts. I guess I'll go for Emacs installed in Nix-on-Droid: it's a Termux with Nix installed. Compared to running Arch in UserLAnd, I lose in the fact that I only have a terminal session, so no graphics, but I win on multiple other fronts, not the least of which is the fact that the Termux's user interface is very screen-keyboard friendly, so I don't absolutely need to have an external keyboard at hand to be able to use my Emacs session.