A very simple Objective-C code example on how to read QR / barcode without any third-party library.
How to use: Open the project using Xcode and build it to your device. Then just try to read a QR Code or a EAN13 barcode. The decoded text will be printed to the console! (so make sure you have your device connected via cable to your computer and keep a look on the Xcode console).
You will not see any change on your device screen when reading a QR/barcode. This is intentional to make the code shorter and as simple as possible.