TileMill
From IFORS Developing Countries Online Resources
TileMill is an open source map design studio, developed by a community of volunteer open source contributors. Original development on the project was led by Development Seed and Mapbox as part of the 2010 Knight News Challenge.
Link to website: https://tilemill-project.github.io/tilemill/
- Up to date information about the software in this list, which is mostly free to use, can be obtained from this link