A study of a small number of phones from the top 3 manufacturers....
"The data we observe being transmitted includes persistent device identifiers (IMEI, MAC address, etc.), location identifiers (GPS coordinates, mobile network cell ID, etc.), user profiles (phone number, app usage patterns, app telemetry), and social connections (call/SMS history/time, contact phone numbers, etc.)," the researchers state in their paper.
"Combined, this information poses serious risks of user deanonymization and extensive tracking, particularly since in China every phone number is registered under a citizen ID."
The Register: Surprise! China's top Android phones collect way more info.
https://www.theregister.com/2023/02/...ones_leak_pii/
Original paper ..
https://arxiv.org/abs/2302.01890