Mobile application Foursquare has released a gorgeous map of the data it collects from users who broadcast where they are to friends. (The startup is using the map of 500 million check-ins to argue that it can provide intelligent recommendations to users even if they don’t want to share their location.) I used the map to examine 10 cities that have particularly striking “footprints” comprised entirely of check-ins by Foursquare users on their mobile phones, revealing the contours of geography, density, and popularity in each locale.
Moscow, Russia

Istanbul, Turkey

Paris, France

São Paulo, Brazil

San Francisco, United States

Melbourne, Australia

Jakarta, Indonesia

Dubai, United Arab Emirates

Madrid, Spain

Los Angeles, United States
