QR code recovery or more than once use.

[niz11]

The issue was already discussed, but was closed because of: "feature decision".

There must be a way to scan your QR code a second time.
Either through some special PIN associated with the QR or through the users phone number: two steps authentication.

Why again?

1. The user can easily lose access to his app for various reasons..
2. QR code are usually not a one time use tool.
3. Users who deleted their test for various reasons.

[dsarkar]

@niz11 Thanks for your contribution.

1. I understand that you refer to PCR / RAT test QR codes?
2. It is currently being investigated how to issue EU test DCC directly to the user (e.g. via email). Such EU DCC certificates (test, vaccination, recovery) can be scanned currently unlimited times and on several devices. This might change in future, i.e. there might be a check and a certificate might be deemed invalid for some reason (e.g. expired).

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Corona-Warn-App Open Source Team

[dsarkar]

see comment corona-warn-app/cwa-app-ios#1198 (comment)

[jucktnich]

I thought about something like this: The user can makes the qrcode scannable again, if he deletes the qrcode from his device

[dsarkar]

@jucktnich The problem I see is the following: If the user was positive and warned others he might do this again from another device. In order to avoid such a situation, if one implemented that a central server keeps track if a user deletes a QR code, so that it can be scanned again when deleted, we weaken bit by bit the decentralised approach.

Of course we will forward this wish-list item again, however, I personally think there is a good compromise already on its way with the EU certificates, which can be scanned unlimited times (unless maybe deemed invalid in a future version of the CWA).

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Corona-Warn-App Open Source Team

[jucktnich]

Ive finally had time to read the documentation and the easiest way would be to generate a qrcode with the registration token and delete it on the old device.

[Ein-Tim]

It should be decided how to proceed here, either answer the question, close the issue as answered (in the comments above) or transform it to a feature request and move to the wishlist.