This is a carrier in the USA (T-Mobile).
I did a quick search for the other 2 carriers using the term “[Carrier Name] Family Tracking” and Verizon and AT&T also seems to have it.
And according to https://www.t-mobile.com/support/plans-features/t-mobile-familywhere-app, it says:
FamilyWhere uses geolocation data from the T-Mobile network and is not affected by changes to device location settings.
So it appears that its using cell tower triangulation. Turning on Airplane Mode should stop it (assuming there isn’t a separate tracking app on your phone)
Oh Wow, What a wonderful tool for abusive spouses and abusive parents. And telecom companies are making money off of it. 🙃
TLDR: Its a good idea to get your own separate cellular plan.
Thats messed up if u can do this without consent of whoever you are tracking.
If you are gonna do this the right way, with consent, there’s probably free apps that can do this (not sure if there are any privacy friendly ones though, but I believe iphones have a tracking feature that’s free).
$10/month is scammy, but they know their target audience ig (abusers probably, like you say).
The counter argument on this is, you need to be an authorized person on the account to enable and considering authorized people are the people who are paying the bill they have full control. In the eyes of the Telecom the authorized user owns every device that’s on the account so they say they want to track it they’re allowed to track.
If you’re worried about privacy and someone tracking you that’s part of your plan, you need to isolate into a separate plan. You lose so many areas of privacy by being on someone else’s plan, like the saving money is nice but they can look up your call history, some carriers allow you to look up SMS history it’s not good
You don’t even need to have the cell on your own account - location data for most any mobile device can be purchased from vendors that sell such data.
There are open-source selfhostable location trackers like Owntracks.