Signal Triangulation Contact Tracing
Phones use cell towers for signal transmission. Via triangulation it is possible to locate phones, and by extension the location of their owners. Some phones have GPS technology imputed in them. This enables precise location of persons so long as their phones were/are on all through; and their phone location function remain on. There might be variations to this function. Some modern phones are CMDA, with no removable SIM card. And many have non removable batteries meaning they would consistently transmit signals so long as they have battery power.
Once an individual e.g with Covid-19 is located it is possible to track the places they visited and persons who were around them for certain periods (and had their phones on). It is possible therefore to use this as an addition to the usual contact tracing that relies on the traditional methods. This technology is widely used, but mainly by governments that Spy on their populations. Use of Wifi or ISP also to an extent helps with location of individuals; there are ways of circumventing this, but all can still be worked out retroactively with “our” teams of computer forensic experts.
Could this approach be in violation of privacy? Yes, but at what point in time does privacy take a back seat so that we advance the common good of the population? Ethical issues are normally shoved aside whenever security/ lives are in danger! Have we reached that point? Probably NOT YET. But it is worth keeping options open if that is the way to go. Already Israel has versions of covert monitoring/surveillance that utilize technologies along such lines. Any electronic devise with internet, radio signal, GPS capability is easily located with reasonable effort. The Chinese government and many others are already using facial recognition apps that are connected to cameras in public places. This is in addition to other aspects of technology not yet made obvious.
If tech experts had wanted to help all recover stolen electronics then they would have done that. But on the flip side the sales would drop; and that is why they never install special chips to help you locate your stolen TVs, Radios, Fridges etc. that the thug stole. Do we have persons interested in making money from such technology? Cows, goats or pets have chips in them, and some of those chips can transmit radio signals! Yes they charge as the cow moves, so they need not be plugged in. Others have special batteries that last over 5 years! In this day and age, how come cars still get stolen?