Privacy-preserving Bluetooth contact tracing
The main function of the TraceTogether App - Privacy-preserving Bluetooth contact tracing - does not need continuous internet connectivity to function.
However, it does require WI-Fi or data connection once a day, to retrieve new temporary IDs from the server, which protects you from malicious tracking.
All TraceTogether Bluetooth contact tracing data stays encrypted and safe on your phone. It is only shared with MOH if you test positive for COVID-19 and agree to upload your data.
There are other features inside the TraceTogether App that will require Internet connectivity on an ad-hoc basis. These include SafeEntry check-ins/outs, SafeEntry history, and checking for Possible Exposures to COVID-19.
If you wish to use these features, your phone will need to connect to the Internet.
Your app will attempt to connect to the Internet (via data or Wi-Fi) in order to perform these functions. The total data usage by the app should be only a few MB per month.