I recently discovered the fun of bump, an iPhone app to transfer businesscards from one phone to another. Like NFC, which Timo has researched in the Touch project (link), this solution is based upon simple, yet effective user interface basics. The user is in control, a physical action is required by both to complete the transaction, and the interaction process is simple to plan and execute. But what makes this more than a simple app is its magic. I still don’t know exactly how it works, and since the app is not available in Norway yet (although a Norwegian language version is available) I haven’t tried it out. But, the magic of bump as an interaction design solution elevates it from useful and usable to desirable.