How the Cell Phone Is Changing the WorldThe modern mobile-phone era dates back only to the 1970s. In just 40 years, in the West, they've gone from suitcase-size novelty to ubiquity. And they're no longer just luxury goods. More than 4 billion of the 6 billion people on earth now have a cell phone, with a quarter of those owners getting one in just the last two years. And many are using them, in a giant global experiment, to change the w
