Do you know if anyone actually used the QR codes? I don't know anyone who has actually used one. Did you have a way to check if it helped having a QR code on there? Or do you think it was you talking to them and your business card that closed the sale, rather than the QR code?
I handed out about 200 cards that weekend and there were about 3 people that scanned the QR code and bought it on the spot (right in front of me... now THAT was cool).
Keep in mind that this is 95% women in this industry, so I didn't expect them to be as "tech savvy" than if I was at a computer conference or something.
I believe that the personal touch of saying, "I built this for someone like you" has a HUGE impact on how people feel about your brand and your app.
Almost... it sent them to my linkshare link that then forwarded them to iTunes (which opens the App Store app on a device). So i gained back that 7% of revenue from Apple that my linkshare referral program gives me. Sneaky, huh?