No cash, no hassle... how smartphone firm is already valued at £26bn... and rising
Uber is the world's largest mobile app taxi service and in the last six months, its value has skyrocketed to £26bn.
It's now one of the globe's biggest technology firms.
Users can use their iPhone or Android smartphone to see what cars are in their area, before dispatching one to their location.
It was founded by Travis Kalanick and the Canadian entrepreneur Garrett Camp in 2009. It operates in more than 200 cities across the world, having grown rapidly by offering cheap rates and a user-friendly smartphone service to find and pay drivers.
Uber also uses a cashless system, with customers signing up with a credit card.
And it's no stranger to hitting the headlines and by no means universally popular.
A protest by at least 5,000 London cabbies last year brought central London to a standstill. Just last week Mr Kalanick defended the company's safety record, as he outlined ambitious plans to create 50,000 jobs across Europe this year and take 400,000 privately owned cars off the road.
Mr Kalanick - who was recently told he could be locked up for two years if he ever visits South Korea - also said Uber was the "safest way around to get from A to B".
In December, the company was valued at £26bn after raising £800m from investors to boost its international expansion.
And as of December 2014, the service was available in 53 countries.
Uber operates a host of different services - from straightforward minicabs to luxury chauffeur services and a 'rideshare', allowing drivers to save on their journeys by sharing with another person.
UberPool lets random passengers share journeys when going in the same direction. But it's Uber's core service which has been operating in Dublin and throughout the UK for the last couple of years.
This week it emerged that Uber is predicted to make $500m in San Francisco alone.