If you are looking for a way to read lots of blogs and web sites from your iPad or iPhone, Google Currents could help. It is an RSS reader that saves content for off-line reading.
Wondershare lets you edit PDFs from a Mac. It is less expensive than the full version of Acrobat. A great classroom example came from an EdTechTeacher summer workshop participant. She created a Wordle, which she saved as a PDF. Then she inserted a QR code into it that linked back to additional information on her blog.
Though an older post, this is still a good starting point for integrating QR codes into the classroom. The Mobile Native is a great blog for integrating mobile devices and focuses on younger students.
In attempts to integrate mobile technology, educators are left to the mercy of app developers who or may or may not fully understand how imperative it is that our children become critical and creative thinkers.
I will highlight apps useful for developing higher order thinking skills
Apps that fit into the "remembering" stage improve the user's ability to define terms, identify facts, and recall and locate information.