Car phones play a major role in the plot of White Heat (1949). A brief discussion here.
We like to think that cell phones and cops tracking radio signals are something relatively recent, but the truth is they have both been around for many decades. White Heat shows the authorities using car phones to communicate with each other while on the road, tailing Cody’s gang. This wasn’t science fiction at the time; car phones already existed in 1949. In addition, they use detectors in the various cars to pick up a radio signal coming from a device on a vehicle to keep triangulating its position as it moves. This is exactly how cops tracked the movement of people via their cell phones decades later (before GPS units became common on phones, which allowed cops an even easier way to track where a person goes.) The presentation of the tracking on screen is accurately represented, right down to the locations around Los Angeles and Long Beach showing up at the right times in the movie.
