A fascinating article in this week's Economist explains how mobile phones can help promote development. The spread of mobile phones has allowed fishermen in the Indian region of Kerala to call while at sea to find out where their catch will fetch the highest price.

This more efficient market benefited everyone. Fishermen's profits rose by 8% on average and consumer prices fell by 4% on average. Higher profits meant the phones typically paid for themselves within two months. And the benefits are enduring, rather than one-off.