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Fed’s new instant payment system could be trouble for PayPal, Venmo
(arstechnica.com)
This is a most excellent place for technology news and articles.
Same in Poland. That, and Blik system which let's you send money to a phone number (if it's also registered with Blik) and it's actually instant. Not "next transfer window" like Elixir transfers, instant.
And yes, completely free.
The US has this, it's called Zelle, every bank seems to have it, and it's instantaneous. For some reason it's just not popular, probably because Paypal and others are already entrenched.