The latest metrics report from mobile advertising firm AdMob claim that 54 per cent of iPhone and iPod touch users are in the US.

26 per cent are in Western Europe according to AdMob's calculations, while 7 per cent are in Asia. In Europe specifically, France, Germany and the UK all have more than 5 per cent of devices.

Meanwhile, AdMob says that the global ratio of iPhone to iPod touch users was roughly two to one.

Apple said this week it's now sold 45 million of the devices, which if you apply AdMob's ratio equates to around 30 million iPhones and 15 million iPod touches. AdMob says the ratio has remained constant in recent months.

AdMob's report also shows that ad requests from Android smartphones were up 25 per cent in June compared to May. The company says Android now has a market share of 5 per cent, having overtaken Windows Mobile.

AdMob's analysis is based on 16.8 million unique users of websites and apps using its mobile advertising platform. The full report can be found here.