QR codes are easy to set up, and offer a range of possible uses for marketers, on product packaging, in shop window displays, in print advertising and more. When used well, they provide a quick response mechanism, and appeal to consumers' curiosity. Whether they will ever become widely adopted is unclear, as there is a potential barrier in that people need to actively download a code reader app first, though there are ways to overcome this. For example, retailers could start to add QR readers to their mobile apps, while there is talk of the iPhone5 having a pre-installed reader. Here are eight examples of how QR codes have been used. Get the full story at Emarketer