[webpayments] Registration: Should we support payee knowing user has payee-controlled payment app? (#112)

At times merchants will want to know whether the user has the merchant's own payment app. 

The payee could do something at registration time to keep track of the payment app. But during payment initiation, how can the payee learn in a privacy-protecting way that the payer has installed the app?

Or does the payee really need to know at the start of payment initiation? What if the payee sends the relevant data through the API in case the payer has the app installed. Then if the user selects the App, communications can take place out of band between payment app and payee. 

Ian

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webpayments/issues/112