Bloomberg LP is launching an app portal to let clients and third-party developers integrate their own software into the company’s financial data terminals. These “specialty applications powered by data and news from the Bloomberg Professional service” can then be sold to Bloomberg’s approximately 315,000 subscribers.

Competing financial data services like Thomson Reuters and Markit have already launched similar platforms for outside applications. The move is unusual for Bloomberg, which has been a relatively exclusive closed system compared to its competitors.

The move is also unusual for Bloomberg, as the Financial Times notes, because Bloomberg is the unquestioned market leader, making the sudden opening of its platform a potential weakness that could compromise its position atop the financial data industry.

“I know a lot of people thought of us as sort of a closed system. Maybe this will make people look at us a bit differently,” Tom Secunda, a co-founder of Bloomberg and head of core Bloomberg Professional service, told the Financial Times.

Bloomberg charges users $20,000 a year for a terminal. While that is certainly a steep cost, it has also helped maintain the exclusivity of its private network—an essential feature for a financial industry always hungry for breaking, market-moving information.

Secunda and Michael Bloomberg founded the company in 1981, before today’s massive network of personal computers could offer similar information without the assistance of something like the Bloomberg terminal. The app portal has been in development for more than a year, the company said.

The benefit of opening up the Bloomberg system to third-party developers is that it could potentially extend the reach of the Bloomberg brand beyond the work-day financial data that has historically defined the media company. Bloomberg said in a statement that the portal is launching with 45 applications “across a variety of categories including, data analysis, news and research, portfolio management and risk analysis, valuation and pricing, data visualization and technical analysis.”

Highlights so far include apps named “Trade Navigator,” “Market Grader” and even “Angry Bonds.”

“Cultivating the third-party developer community is critical to enhancing the user experience and growing the value of the Bloomberg Professional service,” Secunda said in a statement. “The Bloomberg App Portal extends our commitment to embrace innovation and fuel creativity in the financial marketplace.”

The Bloomberg App Portal will behave similarly to Apple’s (Nasdaq: AAPL) iTunes store. Bloomberg will take 30 percent of all purchases made through the app store, though Secunda said that the company did not expect sales made through the new portal to contribute substantially to the company’s current revenue, given how large the media company already is. Bloomberg LP is privately held and does not reveal information about its revenue, but the Financial Times notes that revenues have been estimated above $7 billion.

Also like Apple’s app store Bloomberg promised that the company will use a “stringent developer vetting process” to ensure “the Bloomberg App Portal delivers high-value, exclusive intellectual property, optimized for use with Bloomberg data.”

Bloomberg was hit heavily by the financial crisis of 2009, which has stripped away and increasing number of the core clients of any financial data service. The company has already been adopting its financial terminal to an increasingly mobile environment with tools like Bloomberg Anywhere and an updated version of its core product known as “Bloomberg Next.”