Young people Tweeting from mobile devices are driving the growth of Twitter in Africa, according to How Africa Tweets, a new research launched in Nairobi. In the first attempt to comprehensively map the use of Twitter in Africa, Portland Communications and Tweetminster analysed over 11.5 million geo-located Tweets originating on the continent during the last three months of 2011. This pan-African analysis of Twitter traffic was complemented by a survey of 500 of Africa's most active Tweeters. The study found that South Africa is the continent's most active country by volume of geo-located Tweets, with over twice as many Tweets (5.03 million during Q4 2011) as the next most active Kenya (2.48 million). Nigeria (1.65 million), Egypt (1.21 million) and Morocco (745,620) make up the remainder of the top five most active countries. According to the study, 57 percent of Tweets from Africa are sent from mobile devices and 60 percent of Africa's most active Tweeters are aged 20-29. According to the research, Twitter in Africa is widely used for social conversation, with 81 percent of those polled saying that they mainly used it for communicating with friends. The study found out that Twitter is becoming an important source of information in Africa. 68 percent of those polled said that they use Twitter to monitor news, and 22 percent use it to search for employment opportunities. The majority of those surveyed said that at least half of the Twitter accounts they follow are based on the continent.