Viking is a free/open source program to manage GPS data
... the open-source glide computer
Plugins for OpenCPN
CAD 2D for Land Surveying and Civil
Satellite Emulator
Customization of OpenGTS look and feel
CAD 2D for Land Surveying,Civil and more
Plugin for OpenCPN
a free and open map of wireless communicating objects
GPSBabel converts and transfers data like waypoints, tracks & routes.