Ok do you want to track you or your Car?
Cars (And trucks and SUVs) come in two flavors for this post
Some have GPS tracking already installed (ON Star or On Guard (GM/Ford and contractors in both cases True story follows.
Most cars have an OBD II connector and most cell companies have a device youc an plug into it. IT sends some data to the phone app including location of car.. I'd like to see it send diagnostic data but no joy on the one I tried.
Finally.. if you are worried about your OWN safety. not your car driving off without you.. Your Cell phone most likely has that built in.. Mine has at lest 4 ways... make it 5.. it can be tracked (I forgot Enhanced 9-1-1)
Sadly not all 9-1-1 centers are enhanced thus I have a public URL I can give that tracks my phone if I activate tracking.
Almost forgot story
I'd been briefed on On-Star (totally by accident) when I went to pay my phone bill and walked in on a Sales presentation.
So when I got a BOL (Be On Lookout) for a stolen Cadillac Esclade (They come with OnStar standard) I contacted the entering agancy and gave them the phone number. Inside of 20 minutes I was sending my troopers to an Address... where they found said Escalade. Vehicle recovered.