Unlike radio it is hard for authorities to block mobile signal without severely disrupting the country’s infrastructure and economy. In times of unrest or authoritarian rule the SMS can function as the only source of news. The London-based SW Radio Africa sends out a selection of headlines to 30,000 people in Zimbabwe via SMS.

Full article at the Guardian:

http://www.guardian.co.uk/media/pda/2009/nov/04/digital-media-radio-zimbabwe-...