Testing an iPhone app prototype in class this week was a breeze thanks to some fast paper prototyping. We developed our prototype using the PSD iPhone UI tool available from Teehan+Lax. To give the prototype a bit more of a real feel, we glued color prints to foam core backing to provide a tactile quality not available in pure paper prototypes. While some of our classmates created slick Flash files that could provide fuller interactivity via a web browser, we felt we learned more by giving the test participants something they could hold in their hand. It was fascinating to watch them swipe up and down while telling us how they would scroll through a list of search results in our mobile shopping app. We also learned a lot about what they found confusing when they scanned the mobile “device” and had difficultly with certain parts of the interface. We would have lost that if they were looking at a laptop-based prototype since it sat farther from them than the mobile would in hand. The participants also seemed more engaged by the tactile aspects of touching and holding. After two hours and five tests, we had a lot of insights for the next revision, and all without writing a single line of code.