Does anyone know how to scan a QR code that is on your screen? I am reading a online book with a QR codes and it is to much of a hassle to take another device to scan the codes.
Yes, you can do this without another device:
Take a screen shot of your screen and make sure the QR code is captured properly. Crop to the QR code in the screenshot and save the image file using Preview.
The app will decode the QR and provide you the data.