Bluetooth tracing

Bluetooth tracing is now available on compatible devices. Visit the App or Play store to update to version 3.0.0 if you haven't already.

Last updated: 15 February 2021

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How Bluetooth tracing works

Bluetooth tracing lets your phone exchange anonymous random keys with other nearby phones that also have Bluetooth tracing enabled. If you or another app user in your community tests positive for COVID-19, a Bluetooth alert can be sent to quickly notify any other app users who have been in close contact..

This helps us keep our communities safe without compromising anyone’s privacy.

Bluetooth tracing doesn’t replace our existing contact tracing process and doesn’t remove the need to keep scanning the QR codes. QR codes allow us to create a private record of the places we’ve been, while Bluetooth allows us to create an anonymised record of the people we’ve been near.

Watch this video to see how Bluetooth tracing works.


[Animation showing someone scanning a QR code]

You already know about scanning QR codes with the nz covered tracer app, now the app has an additional new feature called bluetooth tracing.

[Animation showing two people sitting nearby in a cafe. Their phones give each other a digital high five]

It's basically your phone giving an anonymous digital high five to nearby phones who are using the app.

It doesn't know whose phone it is or even where you were meaning your privacy is always protected.

[Animation showing two phones with bluetooth tracing detecting how close they are from one another and for how long]

All the bluetooth tracing function knows is how close the other phone was and for how long.

[Animation showing someone enabling Bluetooth tracing in the app]

Download the latest version of the app and you'll get the option to turn the bluetooth feature on.

[Animation showing phone sending out secure random ID codes]

Your phone will then start sending out private secure random ID codes even when you're not using the app. This is automatic and won't use much battery or any data.

Then when someone tests positive for COVID-19 they can send out an anonymous alert containing all the random IDs they have broadcast over the past 14 days.

[Animation showing a phone sending out an anonymous alert to several phones]

Anyone whose phone has collected one of these IDs will receive an alert and advice on next steps to stay safe.

No information is exchanged about where they were or who they are.

So keep scanning those QR codes Wherever you see them and turn on bluetooth tracing so you can be alerted quickly if you've been exposed to the virus.

Protect your whanau and the community turn on bluetooth tracing.

Turn on Bluetooth tracing

Bluetooth tracing is optional but strongly recommended. The more people who use it, the more effective it will be.

Bluetooth tracing is disabled by default. However, the first time you open NZ COVID Tracer after installing the app or updating it to version 3.0.0 or later, you’ll be prompted to enable Bluetooth tracing. 

You can also turn on Bluetooth tracing or check whether it is already on by completing the following steps:

  • Open the app (v.3.0.0 and later) and tap on ‘Dashboard’ if it isn't already open.
  • If Bluetooth tracing is enabled, the 'Dashboard' will state that “Bluetooth tracing is on”. Otherwise, it will state that “Bluetooth tracing is off”.
  • Tap on the ‘Bluetooth tracing is off’ tile to bring up the option to ‘Turn it on’.
The dashboard in the contact tracer app
Showing Bluetooth currently switched off

Bluetooth tracing and QR codes

It’s important you continue scanning the QR codes wherever you see them, regardless of whether you also have Bluetooth tracing enabled.

The QR codes help you keep a private record of the places you’ve been, while Bluetooth tracing allows you to keep an anonymised record of the people you’ve been near. Both are important for contact tracing.


Bluetooth tracing is entirely anonymous. No personal or identifying information is exchanged between phones, and Bluetooth tracing cannot be used to track your movements.

This means no one will ever see who you’ve been nearby, or when or where you were near them, even if you test positive for COVID-19.

Read more about how privacy is protected in the NZ COVID Tracer app.

Exposure Notification Framework

Bluetooth tracing uses a feature called the Exposure Notification Framework that is built into later versions of the iOS and Android operating systems. The ENF is a simple algorithm that has been developed and published by Apple and Google specifically to improve digital contact tracing efforts around the world.

Read more about the Exposure Notification Framework.

Minimum requirements for Bluetooth tracing

The minimum requirements for Bluetooth tracing are:

  • for iPhones, iOS 13.5 or higher
  • for other phones, Android 6.0 or higher plus support for Bluetooth Low Energy and Google Play Services

Phones with older operating systems cannot provide Bluetooth tracing because they do not have the Apple/Google Exposure Notification Framework.

If you have an iPhone with iOS 10 or later you can still use the NZ COVID Tracer app to scan the QR codes and add manual entries to your digital diary, and you will still receive location alerts if you have them enabled.

Your phone will display this image if it does not support Bluetooth tracing.

Phone screenshot showing a device that doesn't support bluetooth tracing
Phone screenshot showing a device that doesn't support bluetooth tracing


If you believe your smartphone supports Bluetooth tracing but you are having trouble getting started:

  • Check that you are connected to the internet when you try to enable Bluetooth tracing for the first time. You don’t need to be connected to use Bluetooth tracing, but there is an online check that happens the first time it runs.
  • Check that your operating system is up-to-date. Unfortunately, some phones can’t update to the latest version of iOS or Android, but many of them can.
  • It can take several minutes for Android phones to check whether they're compatible with Bluetooth tracing. Please be patient and try restarting your phone if the ‘Checking exposure keys’ message doesn't disappear within around 10 minutes. Do not uninstall or reinstall the app, as this will delete your digital diary.

Read more about using the Exposure Notifications System on Android phones.

Read more about why some Huawei phones do not support Google Play Services.

Please also see questions and answers on the NZ COVID Tracer app.

If your phone doesn’t support Bluetooth tracing

If your phone doesn’t support Bluetooth tracing, you can help keep the community safe by keeping track of where you’ve been and who you’ve seen in other ways:

  • If you have a smartphone running at least iOS 10 or Android 6, you can use the NZ COVID Tracer app to scan the QR codes, keep a digital diary, and get location notifications if you visit a location at around the same time as someone who has COVID-19. 
  • If you have a smartphone running at least Android 5, you can use the Rippl app to scan codes, keep a digital diary, and get location notifications.
  • You can download a copy of the NZ COVID Tracer diary booklet or get a hard copy from your local council’s service centre to help you keep a written record of your movements.

Partial support for Bluetooth tracing in iOS 12.5 

We’re working on supporting Bluetooth tracing for iPhone 5S, 6, and 6+ users who have upgraded to iOS 12.5. 

You can turn on Bluetooth tracing in NZ COVID Tracer on your iPhone 5S, 6 or 6+, once it has been updated to iOS 12.5 and NZ COVID Tracer version 3.0.2 or higher. This will enable the Exposure Notification feature, allowing your phone to exchange keys with other nearby users of Bluetooth tracing. However, these models of iPhones can't yet perform checks of any uploaded keys.  

We expect to make the changes necessary for complete support in the coming weeks. In the meantime, it’s a good idea to turn on Bluetooth tracing and exchange keys. Every extra phone participating in Bluetooth tracing helps.  

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