Singapore was hunkering down for the Lunar New Year holiday in late January when the country detected its first case of the coronavirus. A team of software engineers immediately got to work developing a contact-tracing mobile application.

They moved swiftly and rolled out an app called TraceTogether in eight weeks, making the Asian city-state one of the first countries in the world to develop its own contact-tracing app to fight the outbreak.

When the app launched with great fanfare last month, the government took pains to allay privacy concerns. Officials explained how it uses Bluetooth signals to determine if the user is near another app user and how this data is encrypted and never leaves a person's phone. If someone's diagnosed with Covid-19, the health ministry can ask to access the tracing app's data to identify others who had close contact with the infected individual.

“Please rest assured your personal information is safe in the system. We only collect your mobile number and that's well protected,” said Jason Bay, the engineer who headed the project. He said his team’s vision was to create something akin to a “magic notebook” that follows you everywhere.

Yet the approach raised concerns over privacy and security. Would the data be protected? If the health ministry can call you, is it really anonymous? Citizens had to decide between helping state efforts to protect public health and sharing their personal data, like they are doing now in the U.S., the U.K. and beyond.

So far, the results are underwhelming. Government officials have said they need three-quarters or more of the population to use the app for it to be effective. But just more than a million of Singapore's 5.7 million residents have installed it, and not all of them turn on Bluetooth, a prerequisite for the app to work.

The city-state has had more success with WhatsApp. It approached the U.S. company in late January to explore setting up a communications channel directly with the population to provide timely updates about Covid-19. Now most residents get daily updates via those messages as well as Twitter. Singapore was the first to launch such a WhatsApp service, but now more than 25 countries, including Brazil, Germany, India, Indonesia and the U.K., have followed suit.

As for TraceTogether, the government has made its source code freely available to developers around the world. Japan is reportedly considering using it. Apple and Google have struck a rare partnership to develop tracing apps that work in similar fashion to TraceTogether across iPhones and Android phones.

China, which requires citizens to comply with tracing technology, shows there are pitfalls. The Beijing Health Kit app, which asks local residents to submit names and identification on their mobile phones, assigns each person a color-coded health status that's checked at public venues, including stores and restaurants. On Sunday, foreign passport holders living in Beijing got a jolt for a few hours when the app began erroneously identifying some as having been ordered to stay home for observation. A government spokesman said the issue was caused by a glitch; by the afternoon, the problem had been fixed.

The trade-off between surveillance and public health will become more personal and pressing for all of us in the weeks ahead. Singapore's early start in deploying technology will help others decode the best containment measures for this virus -- whether the tracing app works or not

Tracking the corona virus Singapore style
Leïth Benkhedda