A standard handheld cellular telephone for obtaining diagnostic data is described. In at least one aspect, a standard handheld cellular telephone has a processor, a cellular transceiver, a signal transmitter, a signal receiver and memory for storing instructions for execution by the processor. The acoustic, electromagnetic, optical, and positioning functions of a cellular telephone are exploited. The standard handheld cellular telephone is configured to be capable of performing operations including causing the signal transmitter to transmit a signal through a medium when the signal transmitter is placed adjacent to the medium, receiving with the signal receiver one or more propagations of the transmitted signal after the transmitted signal has passed at least in part through the medium, and obtaining diagnostic data from the received one or more signal propagations.
