in 2007, when Safaricom launched a money-transfer-by-text-message service called M-Pesa (M for mobile, pesa for money in Swahili). The idea is simple: A Safaricom subscriber takes cash he wants to transfer to another person, along with the recipient's mobile number, to a Safaricom agent like Maina. The agent takes the sender's money and, for a small fee, uploads the value to his or her prepaid phone account, then sends on the credit to the recipient's phone account.