MioPocket works on it... download and read the instructions. However I have not figured out how to get Microsoft Reader, which comes with MioPocket, to work with this particular item. I just received a 4.3" unit from the same manufacturer, and it definitely works with MioPocket. Remember that you can use tools and go to the second screen and reset the unit to factory settings to completely get out of MioPocket and not have it load. You can also use autosync to look in the internal flash memory and remove the miopocket material from there... Be certain to look in there before you first install miopocket so that you know what it looks like BEFORE you make the changes.
The GPS uses port 1 at 4800 bps for its connection, internally, from what I've seen, incidentally.