Features
* Easy to use Python API
* Flexible data import options
* Scalable
* Built-in reports
* Built-in data export capabilities
* Open source - easily extended
* Fast processing time (efficient use of graph algorithms)
G. Little, L. Chilton, M. Goldman, and R. Miller. Proceedings of the 23nd annual ACM symposium on User interface software and technology, page 57--66. New York, NY, USA, ACM, (2010)