Online directory of APIs and mashups, ProgrammableWeb, just hit a big milestone this week: 5,000 APIs listed. The site has a long history of tracking the API landscape, starting with the launch of its directory back in 2005, five years after eBay created the first web API. Not surprisingly, big names like Google, Facebook and Twitter are now leading the way in terms of sheer numbers of APIs offered, usage, and popularity. Among developers tracking APIs on the site, Facebook now has the most popular API, and it’s followed by Google Maps and Twitter.
However, according to ProgrammableWeb executive editor Adam DuVander, there were some new trends spotted among the last 1,000 APIs added to the directory, too, including an increasing number of government APIs becoming available.