What's more, the companies say that half of all paid and free downloads on Apple's App Store in these countries are now games, and that depending which country you look at, between 50% and 75% of iPhone owners are playing games on their devices. Across those seven countries, they claim there are more than 63 million iOS gamers who download an average of 2.5 games a month each on their iPhones, iPod touches and/or iPads.

The headline figures: Distimo and Newzoo have focused their attention on seven countries – the US, plus the UK, France, Germany, Spain, the Netherlands and Belgium.

However, separate figures published by analytics firm Distimo and market research company Newzoo show that Angry Birds is the tip of the iceberg when it comes to smartphone gaming, although their research focuses specifically on Apple's App Store. Angry Birds is now a cross-platform success, with a big share of its last 100m downloads coming from Android devices, thanks to the main Angry Birds game being free and ad-funded on Google-powered smartphones (Amazon also struck a deal with Rovio to offer Angry Birds Rio for free on its new Android app store).

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