Mobile money is playing a critical role in promoting financial inclusion in developing countries. Simultaneously, continued price declines are placing entry-level smartphones within reach of a rapidly increasing fraction of the global population. In addition, many of the unbanked live in urban...

Economists have long known that financial services have benefits for users by allowing them to smooth consumption, save for bulky purchases, etc. But the recognition of their importance even for people with relatively low incomes those earning one to two dollars a day, for instance is relatively...