If you mean compilation on mobile, you can compile Nim for iOS, Android or even the Nintendo Switch and this has been possible for years.
If you mean something else (tutorials, tooling, hot-code reloading, ...) can you explain what you want?
On Android:
install termux from google play pkg install nim
now you can compile your nim progs on the phone !
There is currently no mature framework for Nim yet with good learning resources. So you'd do a lot of experimenting and probably run up against a lot of stuff depending on what you want to make. The community is active tho so it's not impossible.
What is it you like to make?
I'm using gtk3+libhandy: https://tuxphones.com/tutorial-developing-responsive-linux-smartphone-apps-gnome-builder-gtk-libhandy-gtk-part-1/
So far the only libhandy wrapper for Nim is https://github.com/StefanSalewski/gintro
Also you can use Unreal to target mobile and as a cross platform environment really. Dont think there is a much better developer workflow for Nim outhere: fast hot reloading with access to the VM as an interpreter too (no comp times).
I want to explore the path of building an example GUI soon. After stripping a few default modules it should be small enough. My bet is somewhere between 30-50Mb not quite sure.
Thanks for the answers, so it might be possible, but it seems to be far from straight forward. So not a lot of progress from where I am standing.
For example: APKs are fairly obsolete in Google land and the list goes on. I might have a look at the game engines, but dragging a big fat game engine for my tiny Nim app around is not very appealing to me.
That's not a lot of progress? Multiple people have had their go, and their results are available for free. Man sometimes I get frustrated with open source.
I understand that shipping an Android app to the Play Store requires an App Bundle https://developer.android.com/guide/app-bundle/ But APKs are not obsolete, how else can you share what your creations among friends?
And besides I don't think it's much work to port any of the existing projects to App Bundles. It just needs someone with dedication.
waiting for others to do things for you is usually a bad idea
But we all try at least once, now don't we? 😉