Is Uber already harming the traditional taxi?

Official figures show that the numbers of people interested in becoming a London taxi driver have fallen and the car-booking phone app Uber is being blamed. But is this the beginning of a serious decline for the traditional black cab, ask Harry Low and Justin Parkinson.

"The cab trade is facing its biggest challenge in 300 to 350 years," says Steve Albasini, who's been driving a London taxi for seven years.

Cabbies in the UK feel under threat from Uber, a US firm which allows passengers to book cars using a mobile phone app, paying by debit or credit card, rather than cash. Its main selling point is that it is cheaper than taxis hailed in the street.

Transport for London figures show the number of people studying "the Knowledge", the geographical training for licensed taxi drivers, fell from 3,326 in 2012, when Uber started in London, to 2,159 last year. Under this system, would-be drivers spend between two and four years imbibing an encyclopaedic level of detail of the capital's streets and traffic systems. They learn about 320 routes, 25,000 streets and 20,000 landmarks and places of interest, such as museums, restaurants, embassies and colleges.

The aim is that, once qualified, they can get a passenger home anywhere in London as quickly and safely as possible. The written exam at the end of their training costs £200 and the practical test another £400. These are in addition to the expense of training, with several Knowledge schools offering courses.

Uber, by contrast, allows drivers to start earning money far quicker. There's no equivalent of the Knowledge - instead there's a reliance on GPS technology to get around cities.

It's a model that's proved popular since the company started in San Francisco in 2009, spreading to 57 countries. Figures released in March show there are now more Uber cars than yellow cabs in New York. In the UK it's expanded into Birmingham, Leeds, Newcastle and Manchester. The business's global value has been placed at $40bn (£25.4bn).

"The figures on London cabs from TFL sound pretty much right," says Steve McNamara, head of the Licensed Taxi Drivers' Association. "Doing the Knowledge is a big time investment. Why would you do two or three years' training, when you have the promise instead of going out and earning instant money? We're very, very concerned about the situation."

MacNamara argues that a growth in Uber vehicles is clogging up the streets of central London while they wait to pick up passengers, also reducing air quality. He claims Transport for London is not doing enough to ensure standards are maintained.

Albasini agrees. "Some people will say 'What's the point in doing the Knowledge?'" he says. "GPS can get you somewhere, but being driven by someone who knows what they're doing is better than being driven by someone who is slave to a piece of computer equipment. That's a bad thing for Londoners."

Ex-servicemen at a taxi training school gaining knowledge of the city

London's taxi drivers have a special term for the quietest period of the year, starting in January, calling it "kipper season". This year, things didn't really pick up again during spring, says Albasini. "I'm working 70 to 80 hours a week," he says, "and I'm just about making the same money I used to from 50 hours a week."

The capital's cabbies are proud of their history. In 1654, Oliver Cromwell set up the Fellowship of Master Hackney Carriages, a name still used for black cabs. The Knowledge test was introduced after the Great Exhibition in Hyde Park in 1851. Visitors complained that drivers were making too many mistakes. The training continued after the first motorised cabs came into use in 1898.

Uber claims that its use of GPS technology alleviates the need for such learning today. Its drivers are vetted to ensure they haven't committed sexual or violent offences, as are licensed cabbies.

Taxi cabs stand idle during industrial action, 1966

After Uber journeys, passengers and drivers rate each other, by giving them up to five stars, based on courtesy, effectiveness and general behaviour. They can leave comments too. Uber says this ensures standards are maintained.

It's not the only rival to black taxis, as minicabs, whose drivers also don't have to learn the Knowledge, have been around for many years and are also regulated by Transport for London.

"We believe we are helping to grow the overall transport pie and offer a complementary service, working alongside iconic black cabs, other private hire services and public transport to keep London moving," says Jo Bertram, regional general manager for Uber UK, Ireland and the Nordics. "The efficiency of our technology helps us offer our services at a competitive price, which means we can attract people who might otherwise have driven their own cars."

As well as protests against Uber in London, there have been demonstrations in cities across Europe. It's banned in Berlin and Madrid, while in the UK, unions in Leeds gathered last year to oppose its launch there.

There have been complaints about Uber's "surge" pricing, where rates increase at times when not enough cabs are on the road. But the company says its app explicitly shows when this is happening and that the reason for it is to tempt off-duty drivers back to work to meet demand.

When an "equlibrium" is reached, the customer's costs start to fall again, it adds. The company apologised last year when the algorithms meant that surge pricing kicked in during a deadly siege at a cafe in Sydney.

Despite the criticisms, Uber's expansion looks set to continue.

For now, Steve Albasini, who studied molecular biology at university before becoming a cabbie, is planning to keep going. "When I got my badge, I felt more proud about that than getting my degree because I worked really hard to get the Knowledge. I love driving a cab around London. Whatever happens, there's no other job in the world like it."

Kipper season

• Quietest time of year for business - usually starting in January lasting a few months

• There are two theories as to why it is so named

• One says cabbies could only afford to eat kippers, which are relatively cheap to buy

• The other is that trade is as flat as a kipper

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