The figure includes paid downloads, in-app purchases and advertisement, as well as subscriptions. According to ABI Research, the figure has nearly doubled compared to 2011.
Apple apps still lead the way and ABI reckons iOS apps make up about two thirds of all revenue, while Google developers are responsible for around one third. Microsoft and Redmond still have tiny shares, but all that could change thanks to Blackberry 10 and Windows Phone 8.
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