Logo CoronaMelder app

How does the app work?

The app sends you a notification if you have been near someone who has tested positive for coronavirus, as long as you were near them for more than 15 minutes. This can help you avoid passing the virus on to other people without knowing it.

  1. The app uses Bluetooth to detect other people around you, as long as they have the app too.
  2. The closer you are to the other person, the stronger the Bluetooth signal is.
  3. You do not need to enter your location, name, e-mail address, telephone number or any other contact details in order for the app to work. The app does not know who you are, who the other person is, or your location.
  4. If you have been near someone with the app who later tests positive for coronavirus, the app will alert you of this.
  5. If you test positive for coronavirus yourself, you can choose to add this information to the app. This is voluntary. If you do this, the app will then alert all the other app users you have been near. The alert will only tell them the day on which they were near somebody who has tested positive. It does not tell them who that person was, or where they were at the time.
My coronavirus test is positive. What happens now?

You can add this information to the app,together with the GGD. If an employee of the GGD calls you with the test result, they will ask you if want to warn other people via the app. If you choose this option the receiver can’t see who you are or on which location you were near each other. You can decide whether these notifications are sent. This is not compulsory, and it is not automatic.

What information is in the notification?

The notification will say how many days ago you were around somebody who has tested positive for coronavirus. The notification does not say who that person was, and it does not say where or exactly when you were near them.

The notification also includes advice on what to do next

  • If you have mild symptoms of coronavirus: arrange a coronavirus test and stay at home until you get the resul
  • If you have serious symptoms, or you are in a higher-risk group: call your doctor.

It also includes a summary of the symptoms that coronavirus can cause, and information about the test. You can make an appointment for a test directly from the app.

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CoronaMelder - How does the app work

CoronaMelder. The app that helps you to avoid unknowingly infecting other people. How does it work? After you downloading it, the app exchanges codes with other phones that are nearby. The app generates codes for every phone. These codes are random and change several times per hour. If you are near to someone else - for longer than 15 minutes - who also has the app, your phones will exchange codes using bluetooth. But not if someone cycles past you in the street… only if you are near to each other for more than 15 minutes. CoronaMelder collects these codes in the app. Codes older than 14 days are deleted automatically. So CoronaMelder has a list of random codes from other users who have been near to you in the past two weeks. But when and how do you receive a notification? Let’s imagine that a week after you went out, another app user – let’s call him Max – tests positive for coronavirus. Together with the GGD, the Regional Public Health authority in the Netherlands, Max can add his coronavirus status to the app. There is a special GGD key in the app. Max passes this key on to the GGD health worker. The GGD health worker enters the key. Now Max can activate the list of codes on his phone. The app users belonging to those codes – including you! – will then get a notification. What’s in the notification? And what should you do next? The notification tells you which day you came near to someone who has tested positive for coronavirus. It does not say who that person was, or where it happened. If you get a notification, it means there’s a chance that you also have coronavirus. The app will tell you what you can do next and whether you should get tested. In this way, new infections can be discovered faster, which helps you to avoid spreading coronavirus to others. Downloading the app is voluntary at all times. We can only get coronavirus under control - together. More information? Visit