Apple and the App Store have near absolute control of the mobile app industry, says Gartner. The research firm notes that approximately 2.5 billion iPhone apps were downloaded in 2009, the 3 billion total downloads mark having been hit earlier this month. By comparison only 16 million apps were downloaded last year through other, newer app stores, giving Apple a 99.4 percent share. Overall industry sales revenue was $4.2 billion.

Apple is expected to slip in terms of relative control during 2010, moving 3 billion apps out of an industry total 4.5 billion, or 67 percent. The App Store would thus generate $4.5 billion of the market's $6.8 billion in revenue, leaving Apple itself a cut of $1.35 billion. The Apple number assumes the company should maintain its current sales rate, roughly 250 million apps per month.

That rate could rise as Apple attracts people with new iPhone models however, and possibly higher if an expected tablet does indeed support iPhone apps. The tablet is rumored to support iPhone 4.0 firmware, which could be announced simultaneously on January 27th.

By 2013 the industry is expected to comprise 21.6 billion app downloads, creating $29.5 billion in revenue. Some 25 percent of the revenue is expected to be generated by "free" apps, in reality supported by advertising. "Growth in smartphone sales will not necessarily mean that consumers will spend more money, but it will widen the addressable market for an offering that will be advertising-funded," says Stephanie Baghdassarian, a research director at Gartner.