QGIS or Quantum: This is a powerful GIS application. It is usually available in the Linux software package but can also be downloaded for Linux, Windows and Apple at http://www.qgis.org/en/site/. Documentation, user manuals, etc. can be downloaded at http://www.qgis.org/en/docs ./index.html. The manuals tend to lag the actual release of the updated software.
Open Street Map and Humanitarian Open Street Maps (HOT) : Open Street Map is not strictly an application, it is an online world map based on satellite imagery on which users can insert features such as roads, rivers, houses using simple software and the underlying digital satellite photography. Open Street Map is available at http://www.openstreetmap.org/#map=5/51.500/-0.100. Training in the simple application software is available on YouTube at http://mapgive.state.gov/learn-to-map/ To find other training search with your browser for "Open Street Map training"You must sign on to modify maps. Humanitarian Street Map (HOT) is a group of volunteers who build maps to help countries deal with humanitarian crises-- for example HOT mapped most urban areas in Guinea, Sierra Leone and Liberia down to the individual building level to assist in the identification and eradication of Ebola in the 2014/15 epidemic. HOT is available at http://hotosm.org/.