(Telecompaper) Over 13.4 billion apps were downloaded from the four leading stores in the first quarter, 11 percent more than in the fourth quarter of 2012, according to Canalys. Direct revenue from paid-for apps, subscriptions and in-app purchases grew by 9 percent sequentially to USD 2.2 billion. Strong growth was seen in mature and emerging markets alike. Apple's App Store accounted for around 74 percent of revenue and Google Play for about 51 percent of downloads.