[skibbityboop]

> Is the sky-link GPS device still sending location data back to a Sky Link server?

As someone who used to work in that industry, no, it's not sending location data. You don't activate the SIM until you have someone who is going to pay for the service, otherwise you're losing money for no reason.

We'd get that question often though, someone activating a device hoping they'd be able to see everywhere it was for the last month.

[m000]

Still not clear. GPS can work without a SIM. Is the device logging locally when the SIM is not activated or not?

If it is then we have a concealed tracking device that can be used against the interests of the car owner at any time. It just happened that EFF didn't have the know-how to extract the logs.

[skibbityboop]

Great question, and yes, some of the better devices implement a small buffer so may be able to keep a day or even two in memory while they're out of cell coverage. If you activate the SIM you might get a small data dump.

GPS doesn't need a SIM, and indeed the devices will have a fix all the time whether activated or not. They do require cell service to send their updates anywhere. They're all simple GPS receivers, not transmitters, thus require an active SIM.