> Does this mean that a user can use their identity on two separate sites, and those two sites can't collude to build a shared profile of the user, without the user's permission?
That's precisely what it means. User IDs will be unique for each site and I'm hoping to anonymize email addresses as well, similar to what Apple has done for "Sign in with Apple". Some companies might be required by law to collect some PII but in that case their needs will be vetted before.
> Does the user have to choose a specific server to be involved in all their identity interactions? If the server stops working, does the user lose their identity?
I'm currently building this as a centralized product so no, there is only a single server maintained by us. I'm mostly concerned with building a great product but the prospect of decentralized, verified identities is also very interesting. I'd love to see what that could look like!
> Also, is it possible to create an account without a phone (or rather without a SIM, since those are often tied to real identities)? Does your proposed system assume that people can't register multiple identities (using multiple phones) if they wanted to?
The current product is in the form of an app so you will need a phone but you won't need a phone number (or SIM). An email address is currently required though.
My current system assumes one identity per person but it's fully possible to have multiple devices which acts as that identity. This might change depending on regulation though and is not set in stone.
If you have any more questions I'd be happy to answer them!
