Most new cars have cell-phone modems built in, providing telemetry back to automakers, since the mid 2010s. That is the dual purpose of the OnStar system, and t

Most new cars have cell-phone modems built in, providing telemetry back to automakers, since the mid 2010s. That is the dual purpose of the OnStar system, and the connections are paid for by the automakers. Because they buy them in such bulk, and have relatively low transmit rates, they get great deals on it.