The application, Health Code 2.0, shows all buildings with confirmed cases in an interactive map for staff to plan routes that minimize infection risks, said Wai Chi-sing, managing director of the authority.

The updated app will be tested by 50 staff responsible for resuming census work this month.

Under its new functions, users can also scan the government's LeaveHomeSafe QR codes to record their visits of indoor venues.

The app can also identify high-risk buildings within 200 meters on an interactive map, as it is linked to the Centre of Health Protection database.

A smart bracelet that connects to the app will remind staff to avoid entering buildings that would put them at high risk of getting infected.

"Workers can get the latest information about the coronavirus as the app updates automatically every day," Wai said.

He said staff may plan their itinerary two weeks before approaching the buildings for land resumption work.

The updated app can also record work details such as the purpose of staff visits to certain buildings, the people they come in contact with and information on events they have attended.

Wai noted that the new version enhances privacy protection.

"The location records would only be sent and saved in the staff's mobile phones instead of the Urban Renewal Authority's encrypted database, reducing the concerns toward privacy leakage," he explained.

Wai added that many countries have launched applications similar to the "Health Code" by using different tracking technologies, which help the administration identify and track the patients confirmed with Covid-19.

"The application is an important development of anti-epidemic measures," Wai said. He also encouraged the government and the industry to work together in promoting this tracking program.

He said the updated app will be used in a big project involving more than 300 workers. The research team will also improve the app by adding Bluetooth positioning technology in the future.