As I understand it:
var payment = new PaymentRequest(methodData, details, options);
- For users, it means potentially better UX. Payment methods are stored by the browser, and work with those browsers existing proprietary payment systems (e.g. Microsoft Wallet). That means users aren’t filling out payment forms nearly as often, they are just selecting payment methods.
- For developers, long term, it means not having to create those payment forms and validating data and all that work. You get the UI and UX of a payment flow for free. Although for now, the best you can do is progressively enhance to this, so it’s more work in the meantime.
- Microsoft has docs for it, and so does Google.