Uber has denied claims that it used its iPhone app to "identify" users even after they had deleted the car-sharing app.
The New York Times reported that the firm's app contained software which kept a record of an iPhone's unique ID, meaning the company could tell if the app had previously been installed and deleted on that device.
Apple boss Tim Cook reportedly told Uber chief executive Travis Kalanick the ride-hailing service would be removed from the App Store unless changes were made because the technique breached Apple's privacy rules.
However, Uber said it tagged devices in this manner for fraud purposes designed to prevent criminals using stolen phones on the service, and had now complied with Apple.
"We absolutely do not track individual users or their location if they've deleted the app," a company spokesman said.
"As the New York Times story notes towards the very end, this is a typical way to prevent fraudsters from loading Uber on to a stolen phone, putting in a stolen credit card, taking an expensive ride and then wiping the phone - over and over again.
"Similar techniques are also used for detecting and blocking suspicious logins to protect our users' accounts.
"Being able to recognise known bad actors when they try to get back on to our network is an important security measure for both Uber and our users."
The report claims Mr Cook summoned Mr Kalanick to a meeting in 2015 to warn him to comply with Apple's App Store rules or have the Uber app deleted from the store.
It was also claimed Uber used code within its software to initially try to hide the feature from Apple.
The ride-hailing service has been hit by a series of controversies in recent months, including the release of video which showed Mr Kalanick arguing with an Uber driver over fares earlier this year.
The company has also seen several high-profile employees depart, including president Jeff Jones and head of engineering Amit Singhal.