I'm quite heavily into the IndieWeb movement, in which we've designed a new standard Microsub which allows for a slightly better API than "regular" RSS/Atom readers, as it allows for you to use different feed formats on the backend. It also splits between the client and the server quite nicely, so I can use Indigenous for Android when on the move, and Monocle when I'm on the desktop. The best thing about the standard, aside from allowing extensible feed parsing, is that I can use different clients to read it, instead of relying on a single provider - which I believe we've seen with some of the RSS/Atom readers around currently.

The server I use is Aperture, built and run by Aaron Parecki, and I subscribe to a mix of RSS/Atom, JSON Feed and Microformats2 feeds