[2] For example, it was estimated that route 15 could have a journey time 4 minutes shorter, due to the number of selective vehicle detection points passed.
[2] The system worked using 'bus detectors' either mounted on lampposts by the side of the road or ground loops, which detect transmission made by transmitters aboard buses.
[3] Selective vehicle detection was replaced by the iBus system in the late 2000s which tracks all London's buses, allowing passengers to be provided with audio-visual announcements and improved information on bus arrivals, as well as triggering bus priority at traffic lights.
[3][4] iBus uses the Global Positioning System instead of physical roadside equipment.
[5] This article related to bus transport in the United Kingdom is a stub.