3G Americas, the GSM trade association, announced that the number of mobile devices active in the world today had passed the 4 billion mark in December 2008, according to an estimate by Informa Telecoms & Media. The number represents more than 60 percent of the world's total population. Release [1]
Links:
[1] http://www.fiercewireless.com/press-releases/mobile-connections-reach-4-billion-worldwide