In some developing countries with little "landline" telephone infrastructure, mobile phone use has quadrupled in the last decade.[20] The rise of mobile phone technology in developing countries is often cited as an example of the leapfrog effect. Many remote regions in the third world went from having no telecommunications infrastructure to having satellite based communications systems. At present, Africa has the largest growth rate of cellular subscribers in the world,[21] its markets expanding nearly twice as fast as Asian markets.[22] The availability of prepaid or 'pay-as-you-go' services, where the subscriber is not committed to a long term contract, has helped fuel this growth in Africa as well as in other continents.