Hi I recently tried out Debian noroot for Android
https://play.google.com/store/apps/d...EebejwSk2LiwDQ.
And found out it is actually very good. Sure don't expect a full debian distro. But it sure is fun to mess with. This version runs xfce desktop. I would not really recommend using it on a small phone(almost to small to display right ) but it should work good on a larger one or a tablet. A mouse is not needed but it makes it a lot easier, same with the keyboard. So if you want debian on the go. try it out.
