HOW long will it be before everyone on Earth has a mobile phone? “It looks highly likely that global mobile cellular teledensity will surpass 100% within the next decade, and probably earlier,” says Hamadoun Touré, secretary-general of the International Telecommunication Union, a body set up in 1865 to regulate international telecoms. Mobile teledensity (the number of phones per 100 people) went above 100% in western Europe in 2007, and many developing countries have since followed suit. South Africa passed the 100% mark in January, and Ghana reached 98% in the same month. Kenya and Tanzania are expected to get to 100% by 2013.