Apple's success with the App Store has, unsurprisingly, led the company's biggest rivals in the smartphone space to create their own online stores due to open this year. According to BusinessWeek, Research in Motion's BlackBerry App World is expected to begin operations next week, with Nokia, Microsoft, and Palm getting ready for their own virtual grand openings later this year.

Mike McGuire, an analyst at Gartner, said "There's going to be a significant counter-­challenge to Apple," while Trip Hawkins, who worked at Apple in the early 1980s before founding Electronic Arts, commented: "This could make the PC wars of the 1980s look like small potatoes."

While the App Store has a commanding lead at the moment, thanks to its 25,000-plus apps and users who have each downloaded more than 20 apps on average, according to BusinessWeek, RIM will fight back by taking 20 percent of the sales, compared to Apple's 30 percent, with paid apps starting at US$2.99, rather than Apple's $0.99.

Nokia, which is on deck with its Ovi Store set to open in May, will offer consumers app listings based on personal tastes, location, and friends' recommendations, in an attempt to answer one major complaint about the App Store, which is the difficulty many users have with navigating its enormous amount of content.

While some developers may be frustrated with that situation, however, it's hard for them to turn away from the potential profits. Satoshi Nakajima, president of photo-editing startup Big Canvas, told BusinessWeek: The distance between Apple and the others is huge. We don't have time to look at other platforms seriously."