There's no Common Lisp or Haskell compiler, for example. Termux is great if it has the package you want, but if it doesn't you'll have to try one of the other solutions.
You can't find the app in the official Google Play Store link. There's also seems to be no online support. No forums on the internet for this at all. Website is outdated.
If you need a X Session vnc gets started with a single click. No configuration needed. Usable on the android host or any other device capable of running vnc.
This emulates an x86 chip on your ARM device, instead of using Linux applications compiled for ARM in the first place. It can even run Windows, but it's slow.
Setting it up takes some effort. And 3rd-party VNC client (or X server) apps might have a better user interface than GNURoot's default. These also work, but also take some effort to set up.