I have spent a good 15 minutes looking around for these mysterious websites that can decode barcodes, and not found anything but this one, which doesn't work on any barcode image file I give it.

I have seen many breathless articles about the Grave Threat To Our Security posed by being able to know ahead of time whether I'll be groped and scanned.

How can I decode a barcode, either on a website or with my phone? None of the barcode scanner apps for iOS seems to read boarding pass barcodes.