Timing as an integral component of modern digital communications and broadcasting signals can be exploited for ranging and positioning beyond their original purposes for urban users. High transmission power, wide coverage, and deep penetration of such signals make them convenient supplements/alternatives to global navigation satellite systems (GNSS) that often fail in such environments. However, there are several difficulties to confront. Ranging has more stringent accuracy requirements on time of arrival (TOA) than communications and broadcasting. Contrary to GNSS, communications and broadcasting signals typically do not carry time of transmit (TOT) and location of transmitter (LOT). Besides, their clocks are not as stable as the atomic ones aboard GNSS satellites. Multipath is detrimental; fading errors can be corrected with redundancy and retransmission in communications and broadcasting yet it is irreversible for timing. Non-line-of-sight (NLOS) signals are helpful to reach shadowed areas in communications and broadcasting but a major ranging error source. A single link suffices for communications and broadcasting, whereas multiple distributed sources are necessary for positioning to reduce geometric dilution of precision (GDOP). A ground vehicle undergoes frequent go-stop-go motions and rapid turns. The positioning filter of a standalone receiver may have difficulty to model such maneuvers yet the integration with an inertial measurement unit (IMU) can help sense the motion directly, fill the data gaps, and reject large outliers, ultimately producing a reliable position solution. To address such issues, experimental digital television (DTV) signal data are used as a case study to demonstrate the performance of urban mobile positioning.