QGIS is a free and open source software that revolves around all aspects of managing and using digital geographical data and is the competitor to ArcGIS. With a GIS application you can open digital maps on your computer, create new spatial information to add to a map, create printed maps customized to your needs and perform spatial analysis.
QGIS is available as a desktop, browser, server, and web client application, and is now offered on Android devices in beta.
For help finding spatial data or other GIS software and tools, check out Demography Research Guide