The mobile phone turned forty this month. Ramon Lobato reviews three recent books about the worlds it has created: 'Moving data: the iPhone and the future of media', edited by Pelle Snickars and Patrick Vonderau, published by Columbia University Press 2012; 'Studying mobile media: cultural technologies, mobile communication, and the iPhone', edited by Larissa Hjorth, Jean Burgess and Ingrid Richardson, published by Routledge, 2012; and 'The Great Indian Phone Book: how cheap mobile phones change business, politics and daily life', edited by Robin Jeffrey and Assa Doron, published by Hurst and Company, 2013.