Was 2010 the year of the API? Some have claimed this each of the last five years, with the next always eclipsing the previous. There were 1,019 new APIs added to our API directory in 2010, two times the number added in 2009. Greater trends on the web are being played out, as social APIs were the most popular and the influence of mobile is clear.

Social APIs were by far the most common type. We can’t discuss social without mentioning Facebook, which made sweeping changes to its platform, launching the Facebook Graph API. With proper user permissions, this API makes a user’s data–including friends and photos–available outside of Facebook.


Internet APIs may seem like a strange categorization at first. Everything in our directory is on the internet? When we refer to internet APIs, we mean the glue that holds the web together. This includes big platforms like cloud hosting services Google App Engine and Amazon EC2. But it also includes 25 URL shortener APIs and 5 domain registration APIs.

Mapping and Mobile APIs were both popular for the same reason: location came to the web in 2010 in a big way. From check-in apps to geographic databases, where a user is (or wants to be) is becoming more important because the internet is now going with many of these users. Mapping has always been a popular category, especially for mashups. The 2,150 Google Maps mashups are almost four times as many as the second place API in our list of popular APIs by mashups. With mobile becoming such a major factor, we’ve seen these APIs move away from displaying maps. Now they include 22 geocoding APIs, 22 geolocation APIs and even 12 GPS APIs for storing and sharing where you go.


Search APIs, like the internet APIs, help hold the web together. Some of these APIs, like the popular Google Ajax Search API, search the whole web. However, in 2010 we saw many cases of vertical search engines making their data available. For example, the novo|seek API opens up a biomedical search engine. The RescueGroups API makes pets available from animal rescues and shelters searchable by organization or location. Each of those is fairly specific, but the overlying trend is making data available in a way that’s easy for developers to integrate.