Using Bluetooth, TraceTogether identifies other nearby phones with the app installed. It then tracks when the device, carried by an individual, are in close proximity with other persons, including timestamps. If the need arises, this information can then be used to identify close contacts based on the proximity and duration of an encounter between the two users.
Once an individual is confirmed with COVID-19, they can choose to allow Ministry of Health (MOH) to access the data in the app to help identify close contacts. While this may not replace the contact tracing process, it is a useful addition – especially when there are problems with recall.
Launched on 20 March 2020, TraceTogether works by exchanging short-distance Bluetooth signals between phones to detect other participating users in close proximity using the BlueTrace protocol developed by GovTech.
The SG Government website provides the following steps:
How do I use the app?
- Enter your mobile number (Step 1)
- Enable push notifications (Step 2)
- Keep Bluetooth turned on (Step 3)
- Leave TraceTogether running! (Step 4)
Should I turn off the app?
- Keep the app running with full permissions
- When DORSCON levels return to Green, the app will stop running, and you will receive an update on how you can delete your data
What about my privacy?
- The app does not track your location or contacts
- Data is stored in your phone for only 21 days and will not be accessed unless you are identified as a close contact
- Measures are in place to protect your mobile number. Your number is paired with a a random ID, and it is this ID that is exchanged between phones, not your actual number
The app is up and running on my phone. What next?
- Make sure to leave it running. If you’re worried about battery life, fret not, the battery consumption is only marginally higher
- If you are identified as a close contact of a confirmed case through the app, MOH will contact you directly. Similarly, if MOH needs to conduct contact tracing with you, they will seek your permission to access the data on your app
- Share it with your friends and family! The app works when there are other users around who have it installed too, so the more people have it, the more comprehensive the info can be
