Microsoft's Windows Marketplace was 80% up on the App Store by the same analysis, with RIM's BlackBerry App World up 43%. Google's Android Market was down slightly (5%), while stores from Samsung, LG, GetJar and Palm were further down. Here's the company's chart:

"Despite all the hype around the major platforms Android and iOS, publishers are still overlooking the hidden potentials of the niche players," suggests research2guidance. Overlooking, or concentrating on an entirely different metric: how much money is being made on these stores? Not to mention how much it costs to develop apps for them.

Download numbers are no guide to how much money is being made. They don't tell you how many apps are being

The second current piece of research that filters into this discussion comes from analyst firm Ovum's new report on mobile apps. It predicts that Android will overtake iPhone this year for the total number of app downloads - 8.1bn to 6bn - with the gap widening to 21.8bn and 11.6bn by 2016.

And the App Stores? Developer payout figures are one useful stat, although so far it's only Apple that has announced milestones like its first billion dollars paid to iOS developers. But the truth is more complicated, taking in the ratio of paid to free downloads, the success of advertising models, the ease and resulting adoption of in-app purchases, and a host of other stats.