Possibly a great bridge between the tradition (analogue?) world and the digital is the Post-It Plus app.
Take your traditional Post-It activity in class – what ever it is. Say, you have asked for a brainstorm of some sorts, perhaps on what the class already knows about a topic. So, everyone (or groups) write down some ideas, one per Post-It and then share them on the whiteboard for all to see.
Now get out the iPads. Open the app and create a new board.
Take a pic of the Post-Its, however they happen to be arranged. The app will identify what is what and then you can start having fun.
Now that you have this image of the Post-Its on your iPad (a single device in the class hooked into the projector or TV or perhaps a class set) students can start rearranging the notes into categories.
That is what Geographers do, right? Debate the different grouping options, organise an argument for and against a question to help formulate an evaluation … really what ever you want.
Now export / share. Beautiful!