Ride-sharing company Uber is to allow its drivers in the UK to receive tips from passengers via its app.
Uber said the feature - first introduced in the US in June - would launch in the UK on Tuesday.
The change follows criticism that Uber was making it unnecessarily difficult for its drivers to improve their earnings.
It was described as "a cynical PR move" by a union representing British Uber drivers.
Uber is also launching a series of changes intended to allow drivers to better control their work flow.
These include "paid waiting time" - in which passengers will pay 20p every minute after the first two minutes if they keep their driver waiting.
Paid waiting time will go live in the UK on 22 August.
Uber said that feedback from drivers had prompted it to make the changes.
"Riders who want to reward great service will now have the option to tip their driver through the app after each trip," the company said.
"This means riders don't need to carry cash if they want to tip their driver."
A spokesman confirmed to the BBC that 100% of tips received via the app would go to drivers, without Uber taking a cut.
Rival service Lyft in the US has offered in-app tipping since 2012 and taxi-booking app myTaxi - available in Germany, Austria and elsewhere - can also process tips.
Other new features for Uber drivers include:
- Two-minute cancellations - riders will have to pay a fee if they cancel after two minutes, instead of five minutes, from being allocated a car
- "No thanks" button - drivers can instantly reject a trip request instead of having to wait 10-20 seconds
- Driver destinations - drivers who want to go to a specific area will be matched with passengers seeking a similar route
- Trip request control - drivers can choose not to receive less lucrative UberX trip requests
"This is a cynical PR move ahead of Uber's appeal next month against last year's employment tribunal ruling in favour of drivers," said James Farrar, Independent Workers' Union of Great Britain (IWGB) United Private Hire Drivers (UPHD) chair.
"Despite its claims, Uber remains completely deaf to the most serious issue facing - excessively long hours earning on average between £5 and £6 per hour."
A spokesman for Uber disputed the calculation on earnings, however.
"Last year UK drivers made an average of £15 an hour in fares after our service fee," he said.
The changes were welcomed by the Association of Independent Professionals and the Self Employed (IPSE).
"These benefits both establish and protect the freedom, control and autonomy that makes self-employment so attractive," said Andrew Chamberlain, deputy director of policy.
Uber drivers have long called for better tipping options.
In April - shortly before Uber offered in-app tipping in the US - the New York City Taxi and Limousine Commission announced plans to require all cab companiesthat take payment via credit card to offer a tipping option.
A petition on the issue was signed by 11,000 Uber drivers.
Source: BBC Tech