You can scan a barcode with your iPhone by using a third-party app. Currently, there are no built-in apps that can read barcodes. Your iPhone can automatically scan QR codes using the built-in camera ...

Avoid downloading third-party apps to scan QR codes.

Amazon has released an updated version of its iPhone app which lets you search for items by scanning their barcodes with your phone’s camera. That means you can walk through a store, pick up an item, ...