Brazil's government-run payments system has become dominant

Sweden has had a similar system for several years before PIX in Brazil. It is also integrated with the digital ID system (BankID). The main difference is that the Swedish system is ran through a private organization managed by all the major banks (and the central bank) in conjunction. So the central bank doesn't have direct access to the transaction data technically.

While the Brazilian system is only interacted directly through your bank application, the Swedish application is a separate application tied to your bank account in the backend. Given the... quality of bank apps this is a huge plus. The Swedish Swish app is MUCH easier to use because it only does one thing. My Brazilian mother does not know how to send PIX because her bank app is very confusing and the PIX option is just one of many.

The BankID system of Sweden though is even more impressive than money transactions, pretty much everything government related (including healthcare, taxes, etc) and most private institutions (bank apps, Swish, digital contract signatures) is done through the unified BankID login.

People raised concerns over privacy, but the main problem really is that since these systems cut out the middle man (Visa/Mastercard) and have no fees you also have no fraud protection which is something to keep in mind when using them. Once you send the money it is gone, the banks will not give it back to you even if you got scammed. It creates a whole sort of scam industry in both countries.

https://en.wikipedia.org/wiki/Swish_(payment)

https://en.wikipedia.org/wiki/BankID

I work in Swiss banking. We also have such a system for payments. Its very popular and used by most people. I keep saying they should use it as SSO, if you can authenticate payments you damn well can authenticate login requests. It makes no sense to go to an online shop, log-in with your shop account or google, and then when you pay, authenticate the payment with TWINT. And banks could even use it to login to their e-banking. Currently literally every bank has its own 'Access' App, that is almost the same but slightly different. And to my irritatingly they don't consistently encode TWINT information the same way into the normal banking transactions.

Our developer phones have like 40 apps on them to log into different test system, its madding.

In our system the pay system is also 'half' branded so you have to download 'TWINT-<bank>' not just 'TWINT'. Making it unnecessarily confusing and its literally the same app (from a user perspective).

It seems this Bank Id is an even earlier system adopted for modern SSO use-case.