Viking is a free/open source program to manage GPS data
An information system for cyclists in Berlin and Brandenburg
Plugins for OpenCPN
Geodesy based library (geodetic and geocentric functions)
CAD 2D for Land Surveying and Civil
CAD 2D for Land Surveying,Civil and more
a free and open map of wireless communicating objects
GPSBabel converts and transfers data like waypoints, tracks & routes.