iOS: Outread is a solid speed-reading app that teaches you how to read faster while also helping you get through your backlog of articles to read on Pocket and Instapaper. Now, the app is also available on the iPad.
Outread for iPad works pretty much the same way as the iPhone version. Once you start reading an article, Outread highlights words in the paragraph and slowly increases speed as you go along. A few other improvements also come along in this update, including a new kind of speed-reading mode called dimming, support for different document types and improved AirDrop support. This is an update to the initial app, so it's a free upgrade if you already purchased the iPhone version.
Outread ($5.49) [iTunes App Store]