Just because many countries started relaxing their lockdown measures doesn’t mean the COVID-19 pandemic is over. It’s far from it, actually, since we’re nearing 17 million cases.

The good news is that nearly 10.5 million of those suffering from COVID-19 recovered. But that still leaves almost six million people struggling to overcome the virus. And tons of new cases are popping up each day.

People are taking precautions to stop the virus from spreading – wearing surgical masks in crowded places, washing their hands as often as they can, disinfecting objects and surfaces they touch frequently, and practicing social distancing. Many of them have also started using contact tracing apps.

If you’re not familiar with them, they’re apps you install on your smartphone. You keep them running in the background, and they alert you if you come into contact with someone who reported COVID-19 symptoms or who was diagnosed with the virus.

Along with that notification, the app also tells you what you should do next – like whether or not you should go to the hospital or just self-quarantine.

In this article, we’ll be taking a more in-depth look at contact tracing apps. We’ll talk about how they work, whether they’re really effective, and if they threaten your privacy in any way or not.

How Do Contact Tracing Apps Work?

They keep a log of where you’ve been and who you might have interacted with or been in close proximity to. To do that, contact tracing apps will either use Bluetooth or location services:

  • Bluetooth – The apps will exchange anonymous codes with Bluetooth-enabled devices in the vicinity. If one user reports COVID-19 symptoms or a positive diagnosis, the app will alert all other users through the shared codes.
  • Location services – The apps use WiFi, cellular signals, and GPS data to keep a log of all the locations users go to (like restaurants or coffee shops). If a user tests positive for COVID-19, all other users who visited the same place as him/her will receive alerts from the app.

How do the apps know someone is suffering from COVID-19?

It’s simple – users have to be honest about their health and voluntarily report symptoms or diagnosis.

Can Contact Tracing Apps Really Stop the Virus from Spreading?

It’s hard to say.

On the one hand, these apps could help lower the number of coronavirus cases in the long run by making people more proactive. They’re also a good way to relax the lockdown and return to our previously normal lives while also staying safe.

However, contact tracing apps also have some pretty big problems:

Voluntary Data

For these apps to be effective, everyone using them has to be 100% honest about the state of their health, where they’ve been, and who they’ve interacted with. Unfortunately, there’s absolutely no way to check that every single user tells the truth or not.

In the end, if one person who is suffering from COVID-19 doesn’t report their symptoms or the fact that they tested positive in the app, the entire contact tracing process fails.


If only a few people install and use contact tracing apps, they won’t be very efficient. They might even induce a false sense of security, leading to an even bigger increase in COVID-19 cases.

In fact, according to this report, around 60% of the population would need to use contact tracing apps for them to really have a noticeable impact. And that’s a pretty huge number.

Governments could force people to use apps like in China, but that will likely backfire in Europe or North America. And the media publishing aggressive stories like this one hurts adoption too.

False Positives

What if someone intentionally lies and says they were diagnosed with COVID-19?

They could do it just to “troll” people, but they could also do it for more nefarious reasons. For example, they might be a desperate business owner who wants to hurt their competitors. So they visit their stores and then lie and say they are infected.

Not only does that turn contact tracing apps into unethical marketing tools, but it also makes people less likely to trust them. After three or four fake alerts telling people to self-quarantine, they will just be fed up and uninstall the apps.

Even if people don’t intentionally do that, the apps themselves can accidentally report false positives. Bluetooth isn’t always able to measure distances correctly, and neither it nor location services can tell if there is a wall or a window between you and the infected person.

False Negatives

Bluetooth inaccuracies can cause the app to register you as being over ten feet away from an infected person when – in reality – you were sitting right next to them or chatting with them.

That’s just one example out of many. The main idea is this – if that were to happen, these apps wouldn’t help stop the virus from spreading. They might accidentally help it spread even more because it gives people a false sense of security, so they’ll be less careful and take more risks.

Can Contact Tracing Apps Violate Your Privacy?

Besides not being 100% (or even 60%) effective, contact tracing apps can also put your privacy at risk.

For example, some apps ask you to share a lot of personal information with them – like your full name, phone number, ZIP/postal code, gender, age, and even profession (the Indian Aarogya Setu app does that).

Some apps might even ask you to give them access to your phone’s contacts. And their Privacy Policies might mention they share your data with private companies and advertisers.

Overall, that’s nothing short of a privacy nightmare.

How to Tell if an App Is Safe to Use or Not

Contact tracing apps vary from region to region. So how does your country rank?

We recommend checking the guide we linked from ProPrivacy. It takes a close look at 54 contact tracing apps from around the world and ranks them according to how well they protect users’ privacy. You might find the app(s) available in your state or country there, and will be able to quickly see if they’re reliable or not.

What Do You Think about Contact Tracing Apps?

Do they seem like a good way to flatten the curve until a vaccine rolls around? Or are they likely to fail because they rely on voluntary information?

Please let us know in the comments or on social media.