An interactive system for lapping transducers has an abrasive surface that communicates with the transducers in order to provide information for controlling the lapping and testing the transducers. The lapping body is preferably shaped as a disk, drum or tape, and communicates with the transducer with a type of signal that the transducer is designed to read and/or write. Thus for lapping a magnetic head or slider to be employed in a hard disk drive, the lapping body contains a magnetic medium layer that is either prerecorded or written by the head during lapping, while the signal received by the head is monitored and analyzed by a processor in order to determine, in part, when to terminate lapping. A series of transducers can be simultaneously lapped while individually monitored, so that each transducer can be removed from the lapping body individually upon receipt of a signal indicating that transducer has been lapped an optimal amount. Transducers for employment in drive systems can also be tested for performance characteristics by utilizing lapping bodies having surface characteristics similar to those found in the drive system.