That UI stinks. Who would know to click on the QR code to open a payment request? A payment request doesn't even involve addresses that are visible to the user, it makes no sense that it is under "send to address".

Hopefully they just have a really big click target and clicking on the address would have worked too, although I admit some clear verbage or a button would probably be better. It is good practice to link images and areas around actions in general, because users do tend to click on them.

QR codes aren't the sort of thing anybody has been trained to click though, there's no other cue to even begin to suggest that it might initiate a payment request. To me that would just be a QR code of a Bitcoin address that is in plaintext to the right of it. Showing me this page I would have said there's no payment request support at all.

Looks like even for handling the older URI protocol they don't underline the linked destination address to send money to unless you hover over it: http://blog.coinbase.com/post/78127728420/support-for-bitcoi...

So destination address could be clickable in this. I think they should keep it underlined, though, personally. I guess even Google is throwing that out lately.

I love Bitcoin Payment Protocol (except for its reliance on the "old" system of CAs), but I am not sure what is the use case here.

Is it just for payments where both sides use Coinbase? That sounds ridiculous, but that's what I see on the picture. And I still don't get which side needs to use Coinbase.

By the way, Bitpay already uses BIP70 - if your mobile application supports it, you just scan the barcode and the URL is included.

The motivation write up here was pretty good for explaining the differences between this and and the usual URI method: https://github.com/bitcoin/bips/blob/master/bip-0070.mediawi...

URI method (what I'm used to from clicking a link to pay): https://github.com/bitcoin/bips/blob/master/bip-0021.mediawi...

It's for both sides. If you are paying a non-Coinbase merchant, and they support the payment protocol, you will see the merchant's name, address, and amount displayed. If you are paying a Coinbase merchant from a non-Coinbase wallet, you will see the address and amount correctly displayed.

If you are paying a Coinbase merchant from a Coinbase wallet, normally you wouldn't use this feature (since you can already log in directly and pay them).

> Is it just for payments where both sides use Coinbase? That sounds ridiculous, but that's what I see on the picture.

No it isn't. The user clicks "send with Bitcoin address", the same as they always have, in order to initiate this flow. Paying from Coinbase to Coinbase uses the other flow, usually.