I generally use Flipboard and the Flip it bookmarklet to curate things I find through Twitter, the Flipboard Technology feed, RSS feeds, or anything on the web.  Here is the magazine I created to keep it all together.  I am impressed by Diigo though and want to investigate it further.

Check these out. Tony Vincent is a great follow on Twitter or Google +. Free apps are great for individual use, but they can be a problem for schools with multiple iOS devices if/when the app transitions to a paid version. Especially if you are using Configurator to manage the devices.