RIM says BlackBerry App World now has 15,000 applications, a figure which leaves it well behind the two leading app stores and also trailing Nokia’s Ovi Store. RIM last released a number in September when it passed the 10,000 apps milestone. The new number, which was released on the company’s official Twitter account, obviously falls short of its loftier rivals: Apple’s 300,000-plus applications on the App Store and the approximate 90,000 apps in Android Market. More closely watched is the rivalry between BlackBerry App World and Nokia’s Ovi Store. Although the latter does not release a figure for the number of apps in its store, apps analytics firm Distimo claims the quantity is around 28,000.

In late November, Nokia revealed that the Ovi Store is now experiencing three million total downloads daily, of which around 2.1 million are likely to be ‘apps’. It also said it had attracted more than 400,000 developers in the past 12 months. RIM last publicised its app download numbers in September when it touted 1.5 million a day. BlackBerry App World is, at least, ahead of Microsoft’s Windows Phone 7 Marketplace (in terms of app availability). Microsoft’s store passed 3,000 apps in late November but is new and growing fast and will likely soon become a major threat to BlackBerry App World.