China said Monday it would retire an app used to track travel to areas with Covid-19 cases, a milestone in the country's rapid turn away from its zero-tolerance coronavirus strategy.

Beijing has effectively thrown in the towel on zero-Covid, last week announcing an end to large-scale lockdowns, mandatory quarantine in central facilities, and a broad relaxation of testing measures.

And the central government is now beginning to unwind years of hardline policymaking, with the state-run "Communications Itinerary Card", which tracks whether someone has been to a high-risk area based on their phone signal, to go offline at 12 am Tuesday.

The "Itinerary Card" was a central part of China's zero-Covid policy, with millions of people required to key in their phone numbers to produce its signature green arrow to travel between provinces or enter events and some public places.

First rolled out in 2020 with a four-tier system that assigned different colors depending on users' predicted level of Covid exposure, it was tweaked multiple times before a final change this year shortened the tracking period from 14 to seven days.

It is only one of a panoply of tracking apps that have governed everyday life in China throughout the pandemic, with most people still using local "health codes" run by their city or province to enter shops and offices.

The changes have been introduced despite a top health expert warning of a surge in Omicron cases that could tear through the country where millions of elderly are still unvaccinated.