Cork board type app that allows students to organize research or a project on their ipad. The free version allows for one board. Online, collaborative version would be Wallwisher
Students can create Trading Cards based on people, places, events...I haven't played around with it yet. Wondering about the ability to export content / share content from the app.
Now that ScribblePress isn't free, this is a great alternative for elementary digital storytelling. Little Story Maker lets students incorporate images from the photo roll as well as record their own audio with their stories - all for FREE.