Google is silently linking phone numbers across accounts — the privacy risks and how to stop them
(www.androidauthority.com)
Google Play Service Google Search Google Maps/Standort Dienste Youtube Gmail Google Ads/Google AdSense Firebase Google Analytics QUIC Browser Fingerprinting Family and friends who use Android and have your number saved in their contacts.
So you think it's mostly driven by Android? Google or rather, Alphabet has a much broader reach.