Although it is more of a technical discussion, this article by The Economist is a worthwhile read as it describes quite well how a new way to deliver information to mobile phones is spreading around the world.
“In America and Europe, three types of bar code, called QR Code, Data Matrix and Ezcode, are likely to become common. The first two are free, open standards. Ezcode is owned by a New York-based firm called Scanbuy, but it, too, is available free, for general purposes. The firm behind it makes its money by charging advertisers and publishers when people use it.
In July three mobile-phone operators in Spain—Orange, Telefónica and Vodafone—agreed to load software that recognises Ezcode. Scanbuy has also signed a deal with two Danish operators and two in South America. In the United States, a Samsung mobile phone, the Exclaim, has become the first to be sold with Scanbuy’s program already loaded.”