BaseMap - BaseMap is the only outdoor app you will ever need. Turn your phone into a GPS, map your outdoor adventures, and interact with the BaseMap community.
KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
GPS Status & Toolbox - Display your GPS and sensor data: Shows the position, number and signal strength of GPS satellites.
Proteus PCB design - Proteus PCB design combines the schematic capture and ARES PCB layout programs to provide a...
HuntWise - THE ULTIMATE HUNTING TOOLSET. With advanced mapping overlays, hunting predictions, GPS navigation, weather forecasting, and more.
QUCS - Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit.