The Helioviewer Objective-C SDK by Helioviewer communicates with the API to access solar data visualizations. Installation is available via GitHub and CocoaPods. Guides explain how to make asynchronous requests to receive code responses.
The ProPublica Forensics API allows access to data from Propublica's investigation into the quality of autopsies across America. The API provides "state and county-level data about coroner and medical examiner systems in the United States." The RESTful API is available in JSON, XML and JSON-P formats. An astounding variety of data are available, from the ratio of autopsies to what is expected, to the number of uncertified pathologists working in a state or county system, and on and on.
As a platform for indexing and analyzing machine data, Splunk has emerged as a provider of a Big Data platform that developers can easily invoke. Now Splunk is starting to build an ecosystem around that platform.