The NewsGator API allows synchronization of feed and item-level data across multiple locations. NewsGator has a few unique features not available in other APIs such as Google Reader, so I will dive right into the unique features.
SOAP now, REST later
The NewsGator API is currently offered as a SOAP interface only but Brent Simmons mentioned future plans for REST support during his presentation at last week’s Emerging Technology conference.
Authentication
An application acts on behalf of a user with a NewsGator account. The account also allows access to NewsGator Online, a web-based aggregator that can be used anywhere.
Locations
Each product using the NewsGator API can establish its own unique location setting to allow separate feed lists for different applications and environments. You may have one feed list on your mobile phone, another list of feeds you track at work, and a third set of feeds you track at home for example. Read and unread status can be set for a feed item across multiple locations.
Centralized updates
Once a feed list is established any application using the NewsGator API can request all updated items across all feeds since the last update. If two million aggregator clients request updates from your site every half hour but reroute through the NewsGator API each individual aggregator will hit NewsGator’s servers instead of your site and NewsGator will poll your feeds for updates on behalf of those two million users. NewsGator communicates the total number of readers subscribed to your feed in the User-Agent field of each request. Feed publishers may ping NewsGator directly to make sure all requesting applications have access to the most up-to-date information.
Current implementations
NewsGator owns a portfolio of products that establish a large footprint on the Windows and Mac desktop. FeedDemon is a popular standalone application for Windows owned by NewsGator and will support the NewsGator API in its 2.0 release, currently in its third beta stage. NewsGator Outlook edition integrates with Microsoft Outlook. NetNewsWire is a popular Mac client with millions of users and will support the NewsGator API in its 2.1 release. NewsGator also has a media center aggregator and an online mobile aggregator.
Given the millions of existing users using NewsGator applications there is a good chance users of other feed aggregators will interface with a NewsGator aggregator and expect a full synchronization experience between applications and devices. NewsGator’s single update request for all modified feed items makes it pretty useful regardless, but the user footprint is an added bonus.
More information
There is an official NewsGator API blog with more details and sample code. Greg Reinacker, NewsGator’s CTO sometimes posts information to his blog that you won’t find documented anywhere else.