FIGURE 7.18 Mobile phone users in sub-Saharan Africa. In the past decade, mobile phone use in sub-Saharan Africa has boomed. By 2016, there will be more than 1 billion mobile phones, including in the hands of even very poor citizens, because of innovations that make it possible to buy service access in tiny amounts. One of the most popular uses of phones in Africa is to move money from one account to another.