Organic Maps is a free Android & iOS offline maps app for travelers
Accurately Locate Smartphones using Social Engineering
Traccar GPS Tracking System
A virtual location tool implemented using the Android debugging API
Lightweight GPS Logging Application For Android
A high-performance, feature-packed library for all your mapping needs
Free Public Transport Assistant without Ads or Tracking
GPS log file viewer and analyzer
Viking is a free/open source program to manage GPS data
GPS navigation software for Windows Mobile & WinCE devices.
... the open-source glide computer
GPS track editor for editing tracks and planning (multiple) day tours
GPX viewer, analyser and editor with official maps, terrain and graphs
A Guide of the Trees of Barcelona City
Simple GPS tracking server
A Matlab software to estimate Euler pole parameters
Open source system for GPS tracking devices
Create, edit view GPX tracks (in the background - online maps)
Minimalistic wide-open GPS-locator/tracker
NMEA 0183 library for Java
Advanced mission simulation and analysis tool
Tool to work on map data, to check the data and generate your own maps
Plugins for OpenCPN