Uber drivers threaten rebellion against the $40bn company

The taxi-app firm calls them the engine of the business, but drivers complain of falling pay, insecure employment and vulnerability to difficult passengers

Most days at midday, Uber's nondescript office in London's King's Cross opens its doors and dozens of men clutching sheaves of driving licences and insurance documents pour in. Many are first- or second-generation immigrants from places such as Afghanistan, Poland, Somalia and Nigeria eager to sign up to drive for the US tech company, whose phone-based minicab-hailing app has transformed the taxi industry in 58 countries.

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