As you probably know NuttX has an advanced graphic library called NX:
http://www.nuttx.org/doku.php?id=documentation:nxgraphics
This graphic library is very good to create complex applications for LCD display, but it has an overhead because it uses a graphic server (think it like a small X Server). Also developing graphic application using NX libs it a little bit complicated since there is not a layout editor for it.
If all you need is some Text User Interface on your LCD, then you can use the Curses support (based on pdcurses) that Mr. Greg Nutt added to NuttX.
See some samples here:
Alan C. Assis 