Over the past couple of years, I've frequently suggested that teachers try out Google Reader as a tool for professional development. Sadly Google is ending support for Reader as they try and focus their efforts on a smaller number of products.
There have been many suggestions around the web as to what the best replacement for Google Reader might be, but I've chosen Feedly as my replacement for the simple reason that, like Google Reader, it can sync my read/unread articles across any device I choose to access them from. The iPad and iPhone apps work well and are aesthetically pleasing (much like Flipboard). Feedly is making the transition for Google Reader users to Feedly smooth and you can log in with your Google credentials and sync your feeds up automatically.
Feedly has apps for both iOS and Android devices.