This could become a cool QR ticketing application based on Meteor and Phonegap.

HTML5

http://www.webqr.com/ https://github.com/LazarSoft/jsqrcode

With Phonegap plugin?

https://github.com/phonegap/phonegap-plugins/blob/master/iPhone/BarcodeScanner/README.md

This didn't work out because of different Phonegap API versions.

HTML5

• blog post
• gist