When comparing Debian noroot vs GNURoot, the Slant community recommends GNURoot for most people. In the question“What are the best ways to run Linux applications on Android?” GNURoot is ranked 11th while Debian noroot is ranked 12th. The most important reason people chose GNURoot is:
GNURoot is a completely self-contained app that cleanly uninstalls and doesn't need root permissions.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Does not require a rooted phone
GNURoot is a completely self-contained app that cleanly uninstalls and doesn't need root permissions.
Pro Includes a VNC client for GUI apps
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.
Cons
Con Android 6.0 not supported
If you have a newer device, this won't work.
Con Can't reinstall after uninstall on Android 4.4 or older
Deleting the app data is possible though. That will free most of the memory.
Con Requires at least 900 megabytes of internal storage
It cannot be installed on the SD card. That's a lot of storage considering it only works on pre-Marshmallow (Android 6) phones.
Con Wakelocks on by default
It drains the battery pretty quickly when running.
Con Requires a lot of manual configuration
GNURoot doesn't hold your hand and isn't even documented very well. Getting anything graphical to run takes some doing.