Developers at MIT’s SENSEable City Laboratory created, together with Ericsson, ManyCities, a new website that explores the spatio-temporal patterns of mobile phone activity. The web tool organizes complex data so that users can visualize the patterns of human movement within a city. A chat board allows users to post their observations, creating a forum where urban planners, demographers, and anyone else interested can cross-pollinate and find creative ways of using the data. Cities available as of October 2015 are London, New York, Hong Kong, and Los Angeles.