Free app for creating business cards with QR codes (with added educational uses)
Many templates to choose from

Student Uses:
Historical figures
Market Street job descriptions
Facts - example: give information from the volcano's point of view
Vocabulary words

Card Setup:
Attach links
Give locations (current location, birth place, etc.)
Attach Google Map link
Choose a template that reflects the person or idea on the card

Requires an account attached to an email address. The teacher can set it up with the iPad email address.
Share business cards with other iPads. Store the cards of others in your Rolodex.
To share, open your business card, choose the QR code and have the other person snap the code with the photo option located within the app.
The link becomes active at that point and allows the other user to explore the site associated with that card.
If the card is updated by the creator, it automatically updates in all Rolodex locations where it has been added.

Website: http://www.yprintit.com/
Templates: http://www.yprintit.com/templates/browse/
There are 4 or 5 templates that are not appropriate for student use. They're not so bad as to avoid the app, but they will evoke giggles from young users.
Video Tutorials: http://www.yprintit.com/index/browse/to/Videos

Create a card for George Washington or Wolfgang Mozart or create the card as if you were the volcano that erupted in Pompeii. Give your location, a simple fact, Google Map link or a link to additional information. If you insert a full address in the address section, it will take you there when you click the Location link. This same idea can be used with vocabulary words. Simply add the vocabulary word to the “Full Name” section then add a link to the definition or give a short definition in the "Other" field. Students could also list an address for the origin of the word.