A system and method for monitoring, configuring, programming and/or diagnosing operation of at least one vehicle includes an on-board unit disposed on the vehicle to send and receive data corresponding to at least one vehicle operating characteristic, a plurality of modular applications, each application having an associated function that processes the data corresponding to said at least one vehicle operating characteristic obtained via the on-board unit, and an interface that allows selection among the plurality of modular applications to create a customized system.