The polar world of the Covid-19 trace application


Covid-19 tracing applications deployed in many countries around the world are in a centralized and decentralized way, with different security ways.

Both types use Bluetooth technology to detect smartphone owners standing close to each other. If someone reports an infection with Covid-19 or contacts an infected person, a warning will be sent to the phone.


TraceTogether application operates under the centralized model in Singapore. Photo: AFP.

With a centralized model, anonymous data is collected and uploaded to a remote server, then compared with the location information that person has been to alert others. This is the method that Britain is pursuing.

The decentralized model gives users more control over information, by storing them on the phone. This is a solution that Apple and Google are building.

Both have their advantages and disadvantages, as well as their own supporters.

According to supporters of the centralized model, this solution can provide the authorities with more insight into the spread of nCoV and the effectiveness of the application. The other group argues that the decentralized method will ensure greater privacy for users, protect them from hackers or even the possibility of government surveillance.

In fact, both have yet to prove superiority at this stage. South Korea, one of the most successful countries to curb the outbreak of Covid-19, limited the spread of the pandemic without the two types of applications. However, they use other methods of surveillance to infringe on privacy more, through location.

When the pandemic began, a concentrated approach was first used. TraceTogether's solution in Singapore was working at an early stage, but then was more difficult to control because the number of people installed only about 20%.

Some experts said that TraceTogether encountered operational problems. This software is often incorrect when in the background on the iPhone due to the way Apple restricts the use of Bluetooth. "We are working with Apple and Google to make the application more efficient, especially for iOS users," a TraceTogether spokesman told the BBC.

Australia, one of the places where the centralized method is applied, launched the CovidSafe application based on TraceTogether, or Colombia also has the same coronApp. However, these software also encountered operational problems and were considered to stop using. "We may have to turn off the contact tracking feature in the coronApp application to reduce the risk when it generates unnecessary alerts," said Victor Munoz, Colombia's presidential adviser.

Other countries are expected to focus on centralized applications, for example, French digital minister Cédric O said the country plans to launch StopCovid in June, but is trying to "force". Apple must participate in order to increase efficiency when the application runs. However, Cédric O is being responded by the French human rights agency, saying it is "dangerous" and blocking deployment.

Norway is also adopting a focus model with Smittestopp, which was released for testing last month in three cities. In addition to Bluetooth, the software also collects location data.

Some developers say that Bluetooth and GPS-combining applications like Smittestopp will give accurate results without the need for Google or Apple intervention. However, it may cause privacy concerns. In fact, according to data from the Norwegian Institute of Public Health, there are 1.5 million downloads of this app but only 20.5% of which are used regularly.

Other countries have opted for decentralized development, but are waiting for Google and Apple to launch an Application Programming Interface (API). Germany confirmed it will deploy the application, while Poland, Switzerland, Austria, Latvia, Estonia, Finland and Canada have similar plans.

"The core reason here is that centralized systems force users to upload data to the remote server, while decentralized solutions don't need to do that," said Dr. Michael Veale of DP3T, the team System development similar to Google and Apple explained. "If you use the app to track disease, it's important that its function still works when you're in another country. Covid-19 does not distinguish borders."