SINGAPORE - Making TraceTogether tokens available nationwide from next Monday (Sept 14) will speed up contact tracing and help overcome several limitations of the mobile app, said experts in technology and public health.
For one, the locally developed token is independent of any mobile platform, noted Mr K. K. Lim, head of cyber security, privacy and data protection at Harry Elias Partnership LLP.
Currently, users of certain mobile phones - such as those with older versions of Apple's operating system or Huawei phones without access to Google's Play Store - cannot run the app.
He also noted that the token is useful for seniors may not be able to afford a smartphone or know how to use one, or children who may not own such a phone. The tokens help these groups come on board the scheme, Mr Lim said.
Professor Teo Yik Ying, dean of the National University of Singapore's Saw Swee Hock School of Public Health, said the success of the TraceTogether scheme depends heavily on how widely used it is.
If only 20 per cent of Singapore's population is on board, the scheme will be just 4 per cent effective. In other words, contact tracers using the programme can expect to pick up only four of a Covid-19 patient's 100 contacts, Prof Teo said.
At present, the TraceTogether app has about 2.4 million downloads, accounting for around 40 per cent of Singapore's population. However, Minister-in-charge of the Smart Nation Initiative Vivian Balakrishnan has said that this is not enough as its effectiveness will need to have more people interacting.
On Wednesday, the Government announced that it will be distributing these tokens to any resident who needs them. Distribution will start next Monday at 20 community centres and clubs in Jalan Besar and Tanjong Pagar, which have a higher proportion of elderly residents.
Estates such as Ang Mo Kio, Aljunied, East Coast, Marine Parade and Sengkang are likely to get their tokens between September and October, while residents in areas such as Clementi, West Coast, Sembawang and Pasir Ris can expect to get theirs between October and November.
People can also go to any active distribution site if they wish to get their tokens ahead of schedule. The collection venues and timings are listed on the TokenGoWhere website.
Each token is registered in the user's name, enabling contact tracers to identify people who have been in close proximity to a confirmed case. However, users' names, identification numbers and mobile numbers are not captured in the token, and are stored in a separate system.
When entering a venue, TraceTogether app users scan the venue's QR code on their mobile phones. However, those who use the token will have to get venue staff to scan the QR code on their tokens. Neither the app nor the token captures data on the user's geographical whereabouts. Instead, they work by exchanging short-distance Bluetooth signals with other apps or tokens nearby. This proximity data is encrypted and stored for 25 days before being automatically deleted.
But both experts also noted that the success of the token depends on several factors, such as whether people have the token with them.
“Just like wearing a mask, you’ve got to form that habit of carrying the token when you go out,” Mr Lim said.
Added Prof Teo: "There will still be operational challenges in terms of triangulating the signals... which of the signals are important for us to isolate and quarantine, and which are the ones that may just be very transient."