The gadgets are being used to gather data about the estimated one billion people who live in shanty towns. The Mobile Metrix project aims to determine how big these communities are and discover what their lives are like. The up-to-date data will be given to governments and aid workers to help fine tune projects trying to help these communities.
"We count the uncounted," said Melanie Edwards, head of the Mobile Metrix project at Stanford University. Ms Edwards said many of the people who lived in the world's shanty towns did not feature on government records, and because of that estimates about the size of these communities and the quality of their lives was often old or wildly inaccurate.