Mobile market research firm Distimo looked at the 300 most popular apps on Apple's App Store and found that downloads of free apps had grown 34 per cent since last year. Downloads of paid apps, however, have grown by just 7 per cent.
Despite just 4 per cent of apps on the download service using the system, 72 per cent of all App Store revenue comes through in-app purchasing, up from just 28 per cent in 2010. Of that figure, 24 per cent was through paid apps, and double that through free apps.

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