One of the bigger challenges with anything having to do with software-as-a-service (SaaS) applications is how quickly they can sprawl out of control. Before most organizations realize it they wind up with multiple silos of SaaS applications that are even more difficult to integrate than traditional enterprise applications.
Our API directory now includes 43 documents APIs. The newest is the Mover.io API. The most popular, in terms of mashups, is the Drawloop API. We list 2 Drawloop mashups. Below you'll find some more stats from the directory, including the entire list of documents APIs.