Android: Barcode Scanner
One of the first apps I recommend is a barcode scanning app. The app I installed was called Barcode Scanner. This app is used to scan QR codes. These QR codes can be used to store contact data, calendar data, and most importantly URL’s.
One of the sites I look to for reviews is http://www.androlib.com/. If you click on any app you will see a code that looks like this:
Once you have Barcode Scanner installed you can scan the code on the apps page and it will take you directly to the app so you can download it.
For a bonus scan the QR code in the banner up top. 
Barcode Scanner: http://www.cyrket.com/package/com.google.zxing.client.android
Categories: technology
So is the QR code to link back to apps? Are there QR codes on products and stuff in stores?
They are to link back to apps. It just stores a URL. I haven’t seen them at stores, but later I will post about an app that scan barcodes on store products.