Research In Motion (RIM) has begun accepting submissions from third-party developers for applications for its ‘Storefront’ BlackBerry applications store. In an announcement on its website, RIM said that it was accepting submissions ahead of a “spring launch” for the store. It has also published a list of guidelines that developers must adhere to. Developers are able to set their own prices for applications and retain 80 percent of the revenue generated from their applications.

Announced last October, the BlackBerry Storefront is set to compete with Apple’s pioneering ‘App Store,’ Google’s ‘Android Market’ and Microsoft’s forthcoming ‘Sky Market’ (tipped for launch next month). Apple announced this week that 500 million applications have been downloaded from its App Store, only a month after revealing that the figure had reached 300 million. The iPhone-related store now boasts more than 15,000 applications for over-the-air download.