How does Hong Kong’s ‘Leave Home Safe’ stack up against global contact-tracing apps in keeping track of Covid-19 infections?

Apart from China’s national health code system, must-have apps for travellers include Hong Kong’s ‘Leave Home Safe’, Singapore’s TraceTogether and Japan’s COCOA
Covid-19 tracking and contact-tracing apps have become essential for many people to safely carry on outside their homes, while observing social-distancing rules

Explainers: Technology

Tracy Quin Shanghai

Published: 7:00am, 27 Feb 2022

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In March, the World Health Organization will mark two years since it declared the Covid-19 outbreak a global pandemic.

Despite the disruptions caused by Covid-19, advances in technology have helped countries around the world fight the spread of the coronavirus, sustain daily life, bolster business and government continuity, and keep people connected.

Coronavirus tracking and contact-tracing apps have become essential for many people to have on their smartphones to safely carry on outside their homes, while observing social-distancing rules.

Here is a list of the major Covid-19 tracking systems to help travellers get around.

People check in using a colour-coded health app at the entrance to a shopping centre in Beijing on November 29, 2021. Photo: Reuters

Mainland China’s national health code system

It is nearly impossible for people in mainland China to travel around without using the government’s colour-coded health app. Green means a person is coronavirus-free, yellow means the user needs to get tested and receive a negative result, and red means a person needs to be placed in quarantine.

This national health code system was initially tested by millions of people in Hangzhou, capital of eastern Zhejiang province in early 2020, when Covid-19 started to spread quickly across the country. The system was developed by Alipay, the payments operation of Ant Group, under the guidance of the State Council. Ant Group is the financial technology affiliate of Alibaba Group Holding, owner of the South China Morning Post.

The system, which can now be accessed on both Alipay and WeChat Pay apps, was subsequently adopted by other local governments nationwide. People’s health code data are managed by relevant local governments and technology companies including Alibaba, Tencent Holdings and Guizhou-Cloud Big Data Industry Co.

While the system may have different versions across the country, its “itinerary code” component has one version. It enables the mainland’s three major telecommunications network operators – China Mobile, China Unicom and China Telecom – to access a user’s location with permission during a 14-day period. Mainland residents are often asked to present both their colour and itinerary codes to enter a public place.

Still, privacy remains a concern. “We are always trading our privacy for convenience, right?” said Ruby Ye, a Shanghai resident. “But you don’t really have a choice to not allow them [to access the data]. You have to present the code if you want to get into your office building or take a train.”

Hong Kong’s Leave Home Safe app

The Leave Home Safe app was initially launched by the Hong Kong government in November 2020 on a volunteer basis, as health authorities moved to trace close contacts of Covid-19 patients. Residents are asked to scan a QR code when they enter various premises, such as restaurants and bars, and receive a notification when another person tests positive for Covid-19 virus at the same location around the same time.

The government has assured users that the data is kept in encrypted form on the user’s mobile device. The app, however, currently does not require personal identification verification and does not have a tracking function.

Singapore’s contact-tracing smartphone app, TraceTogether, is widely adopted in the city state. Photo: Agence France-Presse

Singapore’s TraceTogether app

The city state introduced its contact-tracing smartphone app, TraceTogether, in March 2020. Over the past two years, nearly everyone living in Singapore has the app installed on their smartphones. It uses Bluetooth short-range wireless technology to trace people at risk of infection. Personal ID is stored in encrypted form on the user’s handset.

The app was under the spotlight last year when the government said police can obtain any data under Singapore’s jurisdiction for the purpose of criminal investigation, including TraceTogether data. Legislation later restricted use of such data to certain serious crimes, such as murder and terrorism. All data will be deleted from the server storing it within three to five working days if a user deregisters from the platform.

Japan’s Ministry of Health, Labour and Welfare introduced the COCOA Covid-19 contract-tracing app in 2020. Photo: Shutterstock

Japan’s COCOA app

Japan rolled out its “Contact-Confirming Application”, under the acronym COCOA, in the summer of 2020. Each smartphone with this app generates a random code via Bluetooth and posts exposure notification every 10 to 20 minutes.

The app’s emphasis is privacy. Names, phone numbers or geolocation data collected during its use cannot be seen without the user’s permission by anyone, including government agencies or third parties.

But in February last year, it was reported that a major flaw affected about one-third of users. For more than four months, the app failed to notify Android smartphone users who were at risk of infection.

The Malaysian government’s MySejahtera app allows self-screening for users. Photo: Shutterstock

Malaysia’s MySejahtera app

This government-developed app allows users to perform health self-assessment on themselves and family. It has an automated inquiry that asks, for example, whether a user has a sore throat or is experiencing shortness of breath. In December, the government introduced a new feature that enables close-contact tracing via Bluetooth, similar to those provided by the apps in Singapore and Japan.

Visitors walk past the painting ‘La Joconde’ The Mona Lisa by Italian artist Leonardo Da Vinci on display at The Louvre Museum in Paris on May 19, 2021. Photo: Agence France-Presse

Health pass in Europe

Instead of deploying a contact-tracing app, France has implemented since August last year a health pass at places including cafes, train stations, museums and other public venues. A citizen can get the health pass either through full vaccination against Covid-19, proof of recent recovery from the coronavirus, or a negative test result in the previous 24 hours. Italy also has a similar pass.