S1dewinder, as far as I know barcode readers work in all versions of Android and they are not limited to Android. The iPhone has a barcode reader and so do many other camera phones that don't have Android.
I've seen QR Codes on business cards, brochures, fliers, posters, tickets, t-shirts and I have one on my business website on the contact page.
QR Codes are fun, but your phone won't be limited to those. Almost all packaging (if not all) has a barcode on it. You can scan that code with your phone, then you can choose to be directed to to a website with more information on the product or to a summary which gives the names of stores and their prices for that item. Really cool.