Standard data costs apply when you download the COVID Alert SA app. The app has been developed to keep the download size under 3 MB.
The app is free and does not feature in-app purchases.
Once you have downloaded and installed COVID Alert SA, it runs in the background.
- Bluetooth and notifications must be enabled for the app to work.
- You must have access to a mobile or Wi-Fi network to send and receive exposure alerts.
The app uses Bluetooth signals to exchange ‘random codes’ (random numbers that change every so often) with other COVID Alert SA app users. This happens when their smartphones are within 2 metres of each other for more than 15 minutes. It’s like the devices have given each other a digital handshake. The random codes exchanged at the time of the ‘digital handshake’ are stored in a log on each phone for two weeks.
At no stage is the identity and location of the device users required for this exchange to happen. All that the COVID Alert SA app tracks is the proximity of smartphone devices to one another and how long they are in contact.
When an app user contracts COVID‑19 and a test shows they have the disease, they can anonymously report this information to the app community. Their device then uploads the random codes that the device has on record from the past two weeks to the Exposure Notification Server.
The Server sends these random codes to all of other app users. Each app user’s device runs through these random codes to check for a match between these codes and the codes it has stored in the past 16 days (every time it has come into contact with another device using the COVID Alert SA app). If there is a match, the device notifies the user that there they have potentially been exposed to COVID‑19.
It’s that simple!
When close contact app users receive the exposure notification, they also receive information on what to do next to self-quarantine, and to optimise their health and wellbeing. This all happens in a way that preserves the privacy of every app user at all times.