We've gotten a number of calls and emails over the last couple of weeks because people have downloaded our ID scanning app to their iPhone 4, and have not been able to scan IDs with the camera of their iPhone.
There is nothing wrong with our app or your iPhone. The camera on the iPhone 4 is very weak, and it would take 15 - 20 seconds to scan a driver's license. It was a conscience move by us to not enable camera ID scanning on the iPhone 4.
If you have an iPhone 4 you can get an ID scanner attachment to scan barcode and mag stripe drivers' licenses. Alternatively, you can buy an iPod 5 or iPod 6 to do camera ID scanning. You can get a new one for under $200.
ID Scanners by Bar & Club Stats
72 Allen St. 3rd Floor
New York, NY 10002