I soon discovered this device runs it's apps on Windows Mobile 5 OS. After some searches, I installed the MioPocket suite on a Micro SD card and I now have a nice Win CE platform with lots of goodies (GPS apps too) added to the original navigation "only" system. Now it looks like that (similar device):
Next I thought it would be nice to use this device strapped to my forearm to fill GIS/database forms in the field (I am an archaeologist). This will indeed be possible with the nice CyberTracker software.