For taxis it's location, location, location

Location-based services are coming to London's black cabs, and are being used to bring taxis and passengers together across the capital

The art of hailing a London taxi is being turned into a science with a new service that is one of the first to make commercial use of mobile phone location data.

Several hundred black London taxis have been fitted out with GPS receivers, mobile phones and data transmitters that will eventually allow them to be hailed by anybody in the capital with a mobile phone.

Using mobile phone location data, which can pinpoint a mobile phone to within a couple of hundred metres, service operator Zingo can hook up the caller to the closest available taxi. The idea, according to Zingo managing director Mark Fawcett, is that the potential passenger can then talk directly to the cab driver, describe where they need picking up from and where they want to go. If there is no taxi available then Zingo says so.

Instead of a mini-cab controller, a computer handles the routing of voice traffic on a first-come, first-served basis so that callers speak directly to the cab driver who can tell them before even pulling over to the side of the road that anything south of the river is out of the question. It is the matching of mobile phone location data to GPS location data received from the taxi that enables the server to make the match, and route the call. Location data from mobile phones is not accurate to street level, but it is good enough, according to Fawcett. "It is accurate enough for our purposes because of the voice call -- the passenger gets to speak directly to the driver, so can tell the driver where to pick up."

The idea was conceived three years ago, said Fawcett, but the first trial was launched in November 2002. Some of this delay was due to the challenge of getting access to mobile phone location data from the network operators. Such data is generally seen as very sensitive because it can be used to build up not only a picture of a person's movements, but can reveal data about relationships where, for instance, two mobile phones move from one cell to another at exactly the same moment.

Fawcett said the contract Zingo has signed with the network operators means the data is only used for matching locations. When someone first uses Zingo, they are given the opportunity to listen to the company's privacy policy. "We don't even give the driver and passenger each others' phone numbers," said Fawcett. "The call is routed through Zingo's servers, but if you're a passenger you do have an option to redial a particular cab once you've hung up." Billing for the service is taken care of by the taxi driver: A trip arranged using Zingo will carry a £1.60 surcharge (and the mobile phone call is charged at the national tariff).

Currently, Vodafone and O2 subscribers can use the service. The contract with T-Mobile is being finalised, said Fawcett, who hopes to have Orange signed by the end of August.

So far only a small proportion of the 20,000 plus privately-owned black cabs on London's streets have been fitted out with the Zingo kit, said Fawcett. He's hoping to get many more interested. Although Zingo's parent company Manganese Bronze is the same company that makes most London taxis, the drivers are all self-employed. To make the proposition more attractive to them, Zingo installs the kit -- which includes a mobile phone -- for free.

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