[17] To trace users the Ministry of Health (MOH) issues time sensitive anonymous temporary IDs that are used to identify the patient to all third parties.

[4] Once a user tests positive for infection, the MOH works with them to map out their activity for past 14 days and requests the contact log.

[20] The app was released on 20 March 2020, following 8 weeks of development by Singapore's Government Technology Agency in collaboration with Ministry of Health (MOH).

[1] On 10 April 2020, following the lifting of the embargo on the Google-Apple Exposure Notification (GAEN) system, the developers announced that they had been working with Apple and Google on specifications which would allow for cross-border inter-operability, and had begun to incorporate these new APIs into TraceTogether.

[10][23][25] Instead, a new portable, wearable device, called the TraceTogether Token would be issued to all 5.7 million residents in order to increase the pool of participants.

[33] On 5 June 2020, the Minister-in-charge of the Smart Nation Initiative announced in Parliament that the TraceTogether has been downloaded on a voluntary basis by 1.5 million users, which worked out to only 25 per cent of the population.

[35] More than 10% of close contacts identified by TraceTogether turned positive during quarantine period,[40] the percentage may be low due to Singapore mandating mask-wearing since 14 April 2020.

[41] It was reported on 22 April 2021 that TraceTogether system had identified at least 75 persons who had to be placed under quarantine, but would likely not have been picked up through a manual contact tracing process.

[42] On 7 June 2020, Minister-in-Charge of the Smart Nation Initiative Vivian Balakrishnan announced that the government would be distributing a physical device, named TraceTogether Token, to augment the app.

The physical token helps to increase the optimal number of users required for the contact tracing system to work well, which was 75% of the population.

[56] The distribution strategy would subsequently be changed from manned counter operations to token dispensing vending machines from 31 August 2021 onwards.

[57] Downloading, installing, registering the TraceTogether app and scanning in/out using the TraceTogether-only SafeEntry (TT-only SE) has been made mandatory for all Singaporeans and at all places such as cinemas, restaurants, workplaces, schools and shopping malls for contact tracing purposes.

[65] Additionally, the usage of TraceTogether system would be limited to large events with 500 participants, food and beverages outlets, and nightlife entertainment establishments with dancing facilities.

[76][77][78] This disclosure followed investigations triggered by an inquiry from a member of the public in October 2020, and the filing of a parliamentary question by MP Christopher de Souza in early December 2020, with the 3-month delay attributed to deliberations over the possibility of excluding TraceTogether data from the Criminal Procedure Code.

[79][80] On 5 January 2021, Minister Balakrishnan updated Parliament that the police had to the best of his knowledge by that point in time accessed contact tracing data once in the case of a murder investigation.

[81][82] Following questions from Leader of the Opposition Pritam Singh and Non-Constituency MP Leong Mun Wai, Minister Desmond Tan explained in Parliament on 2 February 2021 that this had happened in May 2020 during the course of the Punggol Field murder investigation, where the police tried to but failed to obtain the TraceTogether data from the suspect Surajsrikan Diwakar Mani Tripathi, who did not install the app in his phone.

[85] Following the announcement, some users deleted the app or left the token at home, while others disabled their phone's Bluetooth or selected the “Pause Tracking” function after checking in.

[86] In the month of the disclosure (January 2021), 350 people requested that their contact tracing data be erased from the government's servers,[87] with the number increasing to more than 1,100 by April.

Balakrishnan explained that this situation was not unique to TraceTogether and that under the same law, other forms of sensitive data like phone or banking records could also have their privacy regulations overruled.

[91] The backlash prompted the Government to introduce the COVID-19 (Temporary Measures) (Amendment) Bill on 2 February 2021 formalising the assurances to restrict police access to investigate for seven categories of offences.

[92] Singapore's reversal of initial promises regarding police access to TraceTogether data was cited as one of the reasons for resistance to the Hong Kong's COVID-19 contact-tracing application, LeaveHomeSafe.