[throwaway35784]

What does the 4th amendment say about non law enforcement persons installing a GPS tracker on my car.

Can I go and buy a gps tracker and install it on your car? If not, why is Facebook or Google or whoever allowed to install one on my phone?

It had nothing to do with the 4th amendment. I can buy a GPS tracker on amazon right now. You don't have to be a cop to install a tracker.

[colejohnson66]

Depending on where you are, there may be laws regarding stalking. The problem is that you “consented” (agreed) to the TOS when you signed up.

[nontoxyc]

Facebook tracks you even if you don't have a Facebook account though. And if I signed up in 2009 did I really agree to sharing location data on a smart phone in 2019??

Completely aside I'm finding how much data my Android phone shares extremely intrusive.