Music Web site Last.fm announced Thursday that asking external developers to build complementary services has led to a boost in audience numbers to about 19 million users globally, who are using its services through applications and widgets on third-party sites, the Guardian reported.

These 19 million users are in addition to the 21 million users who access the site each month.

Last.fm, owned by CBS, opened parts of its services and code to developers in 2003, and has built a formal place for them at build.last.fm, according to the Guardian. Another popular site in which developers build tools for free to increase their profile and recognition is on Facebook.

Richard Jones, co-founder of last.fm, told the Guardian that opening the site up to developers “ allows anyone to create and distribute their own unique slice of the Last.fm experience on their own Web sites and platforms.”

In the future, Jones told the Guardian that the site will be moving onto other platforms, such as mobile, games consoles and partnering with other media platforms, “to guarantee that Last.fm continues to drive the best music discovery and listening on the Web.”