I think both Mark and Kevin made some really good points. I find the Sensor vs QRCode debate pretty interesting. There are pro's and con's on both sides. I agre

I think both Mark and Kevin made some really good points. I find the Sensor vs QRCode debate pretty interesting. There are pro's and con's on both sides. I agree with Mark that the sensor (or sensor like) User Experience is much smoother and more natural than scanning QR Codes. The time investment is lower, and it's just plain easier for consumers to understand / use. However, sensors have a physical proximity requirement (aka range). What if the consumer is out of range? Another potential issue for sensors; The automated nature of sensors creates a potential for excessive push abuse. Just imagine your phone beeping every time you walk past a store in a mall and you can't stop it from happening. There are other issues that affect both Sensors and QRCodes, such as security. If I remember correctly, I think a few people experienced this at Defcon (scan the QRCode, infected with malware). Same could be said for sensors (hypothetical of course, but imagine a sensor pushing malware to you automatically?). These are or will become real issues. I think Kevin had some good points about the Business Model, it was pretty unclear to me as well. If fact, I didn’t even know it was a paid app until I read this article. And even then, I think investors prefer a reoccurring revenue model over the one-time payment. Anyway, very cool for them, and I wish them success. My only gripe with the whole thing was the Design. Maybe it's because I'm a Designer, but I was not impressed at all by the Design.