In iOS we can only use something like ish.app which emulates x86 and runs full Linux distro instead, with predictably much lower performance than Termux (due to JIT being banned in iOS apps), but without any restrictions Android has on the executables
iSH is great as an ssh client. It has a good font out of the box, so it displays tmux and neovim properly.
a-Shell should be faster than iSH for local stuff since the tools are compiled natively, but nothing on iOS, as far as I know, compares to Termux on Android.
Elsewhere in this thread, someone mentioned that ISH is a full PC emulator running Alpine. You wouldn't necessarily need JIT or native execution for a software VM.
UTM can't be installed from the App Store unfortunately, and without a developer license you are limited to 7 days for each successful on-device reinstall
Nice, I must've missed that. Downloading it right away :)
Edit: well, it's also very slow unfortunately. I believe iPhone CPUs either don't support virtualisation or they don't expose it (edit #2: it's the latter). Either way, QEMU is struggling quite a bit, and due to it being a GUI it's even slower than what iSH could do