Signal Will Let You Sign Up Without a Phone Number — For $3

You mean they want to identify you from your credit card instead of your phone number? Bah.

They claim it’s “zero knowledge” proof through Google pay, meaning that Google will know you paid Signal, and Signal knows you paid them, but there is no link between the two that uses your PII payment info to identify the Signal account. I’m inclined to believe them.

Unless you wait a good while to use what you paid for (if that’s even possible), then I doubt it’d be hard to connect the dots. Never mind connecting transaction records.

It’s the exact same privacy protection as signing up with a phone number.

Not quite. With a phone number a random phone provider knows your identity. They do not get notified you are signing up for Signals. Google doesn’t know you signed up with that phone number for Signals either. Depending on your country and how these details are handled there may not be an easy way to lookup who you are from a phone number.

There’s obvious downsides to the phone number use, of course, but saying it the same in terms of privacy than this, doesn’t feel correct.