Uber drivers across the UK and US go on strike today (Wednesday) in protest over pay and working conditions.
The United Private Hire Drivers branch of the Independent Workers Union of Great Britain (IWGB) said the strike will last nine hours from 7am until 4pm, during which drivers will not even open the app.
It comes just days before the taxi-booking app floats on the stock exchange for the first time after being valued at $90 billion.
James Farrar, chair of the United Private Hire Drivers branch of the IWGB, said: "It is the drivers who have created this extraordinary wealth but they continue to be denied even the most basic workplace rights.
"We call on the public not to cross the digital picket line on 8 May but to stand in solidarity with impoverished drivers across the world who have made Uber so successful."
The IWGB said its drivers want to see commission to fall from 25% to 15% and fares to rise from £1.25 to £2 per mile.
A spokesperson for Uber said: "Drivers are at the heart of our service - we can't succeed without them - and thousands of people come into work at Uber every day focused on how to make their experience better, on and off the road.
"Whether it's being able to track your earnings or stronger insurance protections, we'll continue working to improve the experience for and with drivers."