From the Nov 12th 2009 Economist: Iraq's mobile-phone revolution Better than freedom?

During recent years of civil strife, when many stayed indoors, mobile phones were the lifeline. They also became a tool of commerce. Reluctant to risk their lives by visiting a bank, many subscribers transferred money to each other by passing on the serial numbers of scratch cards charged with credit, like gift vouchers. Recipients simply add the credit to their account or sell it on to shops that sell the numbers at a slight discount from the original. This impromptu market has turned mobile-phone credit into a quasi-currency, undermining the traditional informal hawala banking system.

The market’s growing size is making some bankers wonder if phone credit should be traded on a public exchange. This may not be practical, but more regulation would be welcome. Criminal rings are among the parallel currency’s busiest users. Kidnap gangs ask for ransom to be paid by text messages listing a hundred or more numbers of high-value phone cards. Prostitutes get regular customers to send monthly retainers to their phones, earning them the nickname “scratch-card concubines”, while corrupt government officials ask citizens for $50 in phone credit to perform minor tasks. Viewed as cash substitutes, scratch cards have also drawn the attention of armed robbers. In one case, a gang emptied out the card storage of Iraq’s biggest mobile operator, Zain, which is based in neighbouring Kuwait.

Not to be left out of the bonanza, Iraq’s cash-strapped government now says it will sell a fourth mobile-operating licence, after raising $1.25 billion from each of the last three. That is less than its vast oil reserves promise to put into the state’s coffers but a lot easier to negotiate. And Baghdad is not the only place where mobile-phone commerce thrives. The UN says it has plans to deliver aid to Iraqi refugees in Syria in the same way.
From the Feb 22nd 2008 Economist: Bringing the poor online, It won't be as easy as providing mobile phones

THE mobile-phone industry returned from its mammoth annual trade show, 3GSM, held earlier this month in Barcelona, gloating over its successful year. More than 3 billion (almost half the world’s population) now have mobiles, and the price of a phone has sunk as low as $25. There are now more mobile-phone subscribers in poor countries than rich ones. That would have been unimaginable a decade ago.

Mobile phones have improved poor people’s lives tremendously, from providing political news and health-care information in remote areas to fuelling commerce. Enthusiasm over bringing technology to the world’s poor has been matched in the computing industry, with many companies now selling low-cost laptop computers (so far around $200, but poised to drop much further). But the next digital hurdle—providing internet access—will be much harder to surmount, for both economic and geographical reasons.
Mobile-phone usage is inexpensive because the networks are cheap and easy to build. Equipment is priced low due to rabid competition (particularly from Chinese makers). The capital expenditure differs, too: coverage is built piecemeal as subscribers swell, bolstered by generous vendor financing. And almost all subscribers are on pre-paid plans, so operators collect money before the first call is connected.