It is great to see research of this nature hitting the airwaves of Nature.

The authors have done a great job in providing a convincing argument with data over a 15 month period and 1.5 million records.

Source: http://www.nature.com/srep/2013/130325/srep01376/full/srep01376.html

Source: http://www.nature.com/srep/2013/130325/srep01376/full/srep01376.html

I've gone through the list of references and have found many that we have previously cited in our own work which provides additional confidence in the literature reviewed. For example, see the work of Roba Abbas in the special issue in the Journal of Location-Based Services of Dec 2011 here where similar data of a small-scale trial of real users was depicted using GIS for representation and scenarios. Roba's PhD was part of an Australian Research Council Discovery grant on Location-based services Regulation in Australia that received a high commendation on completion. Other papers that could add inspiration to the paper in Nature for those seeking additional references include papers submitted to this special issue as a whole that included individual submissions by Hamed Ketabdar of Deutsche Telekom Labs, Clarke & Wigan of Australia, Michael and Michael's editorial which is still the most read article in JLBS according to Taylor and Francis Online, among others .