With technology playing an increasingly important role in confronting the COVID-19 pandemic, Bluetooth-based apps are being deployed across multiple countries to boost contact-tracing efforts – which are crucial to slowing the spread of the disease.

Many of these apps are built on Apple and Google’s exposure notification framework. The tech giants announced a collaboration in April this year and have since worked together to help governments, health agencies and non-governmental organisations to curb the spread of COVID‑19.

The Apple–Google Exposure Notifications application programmable interface (API) has been used as a base on which to build customised apps across multiple countries. The apps use the Bluetooth capability on smartphones to carry out contact tracing for COVID-19. User privacy and security are at the core of the design.


Download South Africa’s new COVID ALERT SA app

Like many countries the world over, South Africa’s National Department of Health has used Apple and Google’s exposure notification framework to build the new COVID Alert SA app. The app is now available to any person in South Africa.

You can download the app from the Apple App Store or Google Play Store.

  • Downloading the app is quick and easy – it’s under 3 MB in size.
  • The app is free and does not feature in-app purchases.
  • You will not have to pay for mobile data when you use the app – the data to use the app has been zero-rated by all of South Africa’s mobile network providers.

COVID Alert SA app is one of various offerings that form part of COVIDConnect – the South African government’s official COVID‑19 digital support service that launched on 17 July 2020.


What is Bluetooth technology?

Bluetooth wireless technology has been around for about two decades. It is the technology we use to connect Bluetooth-enabled devices to each other – such as our smartphones to our cars, or to fitness devices, wireless speakers, headsets, earbuds and other devices.

By design, Bluetooth is constantly reaching out to other Bluetooth-enabled devices using Bluetooth radio waves. In essence, Bluetooth devices are constantly broadcasting their presence to each other. That’s why devices that have previously been paired ‘recognise’ each other and automatically reconnect using Bluetooth when they are in close range of each other. If the devices that have Bluetooth do not recognise each other, they do not pair or link to each other when they are in close range.


What is contact tracing?

 Contact tracing is the process used by public health authorities to control the spread of epidemics and pandemics. It’s been integral to containing outbreaks such as that of the Ebola virus in 2014, of the 2003 severe acute respiratory syndrome (SARS) outbreak, and of tuberculosis (TB) and other infectious diseases that are highly contagious.

Contact tracing means healthcare workers identifying and interviewing those who have contracted a disease to identify their ‘close contacts’ – those they have been in close proximity to in the recent past and therefore possibly infected as a result of their close contact.


Why do we need to identify those who have been in close contact with someone who has COVID-19?

In the case of COVID-19, close contacts can be guided to self-quarantine for 14 days and monitor themselves for symptoms. If a close contact develops symptoms, with the knowledge that they may have been exposed, they can interact with a healthcare expert to seek the right medical assistance while also protecting others from the disease.

Contact tracing is so important our world right now. Many people who contract COVID-19 have no symptoms (are asymptomatic) or experience very mild illness, and so do not know that they have it and that they are exposing others to the virus. They also do not know if they’ve exposed someone who is at high risk of severe illness if they contract COVID‑19. High-risk individuals are people who are possibly immunocompromised (such as those who have HIV or TB, cancer survivors and transplant recipients), those who have chronic illnesses and those over the age of 60.


Why do we need apps to assist with the contact tracing process?

Contact tracing is a time-consuming, manual process that has its limits as the person who tests positive for COVID-19 needs to remember all the people they have been in close contact with for the past two weeks and their contact details, which is not possible for people they come into contact with in public places such as the grocery store or public transport.

Bluetooth contact tracing apps, like COVID ALERT SA, replace the need for us to remember and identify close contacts by simply letting app users’ smartphones “say hi” to each other and keep a record of all the times this happens.

And, app users’ identities are kept private at all times.


13 simple steps: Here’s how the COVID Alert SA app allows for Bluetooth contact-tracing

  1. The COVID Alert SA app uses Bluetooth signals to exchange ‘random codes’ (these are just random numbers that change several times a day) with other COVID Alert SA app users.
  2. This happens when app users’ smartphones are within two metres of each other for more than 15 minutes.
  3. This process happens when app users are near to people that they know – such as when near to friends, family or colleagues – and people that they aren’t acquainted with – such as at the shops in a queue, or on public transport.
  4. As long as the COVID Alert SA app is running on smartphones that are near enough to each other, they will share random codes – almost like they have given each other a digital handshake.
  5. The random codes exchanged at the time of the ‘digital handshake’ are stored in a log on each phone for 16 days.
  6. 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.
  7. Then, when an app user contracts COVID‑19 and a test shows they have the disease, they can choose to anonymously report this information to the app community. That kicks off the Bluetooth-based contact tracing process.
  8. Their smartphone uploads the random codes that it has on record from the past 16 days to the Exposure Notification Server.
  9. The Server sends these random codes to all of other app users.
  10. 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).
  11. If there is a match, the device notifies the user that there they have potentially been exposed to COVID‑19, with the date on which they were in contact with someone who has tested positive.
  12. App users also receive information on what to do next to self-quarantine (for 14 days), watch for symptoms of COVID-19, and to optimise their health and wellbeing.
  13. This all happens in a way that preserves the privacy of every app user at all times.


It’s clear that by joining other COVID Alert SA app users, we join powerful community of people who want to work together to Stay Safe, save lives and turn the tide on COVID-19 in South Africa. The power is in our hands. Let’s join the COVID Alert SA community today and play our part in keeping one another safe.