Signal has started rolling out Signal Login, an optional registration method that allows users to create a Signal account without providing a phone number. The feature will be rolled out first on Android and will come to iOS later.
As we previously reported, Signal Login is not a free alternative registration method. Signal requires users who choose to register without a phone number to make a one-time payment. The price at launch is $2.99 / € 3.49, although this may vary by region and currency.
Google can, since it’s their OS and their payments.
But even if you’re not using Play Store to pay, the vast majority of people who are paying are going to be using the same device/IP/fingerprint/etc. where Signal is running, so it’s not impossible to put the two together to link an account to a specific payment, if say, a government forced them to do so in order to track someone. It’s just a bad idea for several different privacy reasons.
Google can know you’ve paid but they can’t link it to your Signal account thanks to zero-knowledge proofs.
Except for tracing IP addresses, timing etc… as you’ve mentioned, but that’s much more involved and cannot be done retroactively.
They can… as I said they control the entire OS. They can see you’re running Signal with account# XYZ, that you clicked the pay button, that Signal generated the ZKP (which they can read in memory or network packets), and all the key clicks and numbers entered of the payment details for that ZKP, the entire process.
That’s just conspiracy theories at this point. If you assume google is constantly spying on the memory of all applications on your phone there is no reason at all to believe that.
I never said they were doing it or that people should assume it, just that it’s possible. Whether or not that matters is up to each individual’s own threat model and should be weighed accordingly.