X Window with GNURoot
If you install Pelya’s XSDL Server from Google Play, you can use X11 aplications. In GNURoot type:

apt-get install xfce4

It will install the XFCE4 Desktop Environment and Xorg with some utilities.

And after several minutes of packages downloading and making configurations, start XSDL and set your favorite display resolution and zoom, and then type in GNUroot:

DISPLAY=127.0.0.1:0.0 startxfce4

Switching to XSDL app, the XFCE4 starts and you can now use the graphical interface.

I found this solution at: http://www.r-ohjelmointi.org/?p=1434

Some other things: 
* Change font size as in ordinary Gnome. 
* Moving a flat finger is same as click and drag, for resizing etc.
* I have to press the back button on the pad to get the screen keyboard displayed. This overlays lower part of X Window though.
* No terminal emulators seem to work properly. However, GNURoot can be used for that.
* Applications like Gnu Planner, gretl and Gnu Cash work without problems.