I thought the phone number was optional?
Discussion
They are, you can select with number or not or just data
There is always a phone number whether it is enabled for voice and text or just data. In addition though, there are other unique numbers associated with your sim and IMEI is the one your phone sends to every tower to handshake with to receive service.
Yeah I don't see a number. Anyways I was referring to the IMEI which is a unique identifier.
Yeah nothing we can do about that unfortunately
There is a mitigation provided by PGPP, it uses a zero'd out IMEI, and some other cool things to thwart triangulation, reducing the precision to an area instead of a pinpoint. I think an important factor is number of users for the "hide in a crowd" effect, and I don't know anything about how many users they have. Also I want it to be open source but given their background I doubt it ever will be, it would have to be re-implemented based on their white paper.