Quick Response (QR) codes are supported by many iPhone apps, but iOS has no built-in ability to read or generate the codes. The jailbreak tweak NativeQR seeks to change all that, by adding native QR code support to iOS. After installation, the stock Camera app will include an option to Enable QR in the same menu as HDR and Panorama.
Turning this on makes it possible to scan and recognize a QR code directly with the camera, no third-party app required. As soon as a QR code enters the field of view and is recognized, the link appears and an option to copy the text is presented. If you're not interested in the QR code just tap Cancel. No special action besides focusing on the QR code with the camera is required.
Besides the ability to read QR codes, NativeQR adds another way to share contacts with the iPhone. Instead of sending an email or message, the tweak can generate a QR code for the contact you're looking to share. Tapping QR Code in the Share Contact menu displays a large QR code on the iPhone display. The recipient of the contact info can scan your screen to read the QR code and gather the information.NativeQR is available on Cydia from the BigBoss repo for $1.99. Check here for instructions on how to jailbreak iOS 6.x with evasi0n. You can also find out how to purchase and install Cydia tweaks with this guide.