Reference to this hidden feature was uncovered by 9to5Mac while going through the operating system’s code, and was not found in the previous version of the beta. The site reported that they’ve managed to access the new Apple Pay ability, but were unable to get it to work due to it not being implemented yet.
They noted that the feature will enable users to either scan a QR code to conduct payments, or display it on their phone’s screen to be scanned during checkout. 9to5Mac added that this would also allow some kind of interaction with third-party applications, as the code was discovered in a public system API within iOS 14. Since the payment via QR code function was not announced or demonstrated during the recent WWDC 2020 keynote, it’s very likely that Apple is still working on it before making it available for testing. It is unknown if the company is planning to implement this feature alongside the launch of iOS 14 later this year. (Source: 9to5Mac)
