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how app works

How the MI COVID Alert app works

MI COVID Alert is a free app for your mobile phone. It will help us to protect each other and slow the spread of coronavirus (COVID-19).

If you use the app you will:

  • be told if you may have been in close contact with another app user who has tested positive for coronavirus
  • be able to anonymously warn close contacts if you test positive for coronavirus
  • make contact tracing quicker for the health service
  • help map and predict the spread of the virus

Why use the MI COVID Alert app


Contact tracing finds people who may be at risk from coronavirus because they were in close contact with someone who has the virus. They can then be alerted and advised on what action to take to protect themselves and others.


The app is part of our contact tracing operation. It uses Bluetooth and anonymous IDs to log:

  • any phone you are in close contact with that also has the app
  • the distance between your phone and another app users' phone
  • the length of time your phone is near another app users' phone

Every 2 hours the app downloads a list of anonymous IDs. 

If you have been within 6 feet of someone for 15 minutes or more and they anonymously share a positive COVID-19 result, you'll get an alert that you may have been exposed.

The app does this work in the background. This means you can use your phone as normal. MI COVID Alert mobile app close contact notification


If the app finds that you have been in close contact with someone who has tested positive for coronavirus, you will get a notification. The notification will appear in 2 places. This is to make sure you see it.

  1. The notification will appear on your phone's home screen.It may disappear from your phone after a period of time if your phone thinks you have seen it.
  2. The notification will also show within the app. This is to make sure that if you miss the notification on your phone, you can still see it in the app. This notification will not disappear. It will remain within the app on your phone.


If you are unsure if you received a notification or think you may have missed a notification, open the app and check for notification. If there is a notification when you open the app, you have been in close contact with someone who has tested positive for COVID-19. The notification will advise you on what to do next.


You'll be asked to give the app permission to use Bluetooth on your phone. Bluetooth needs to remain on for contact tracing to work.

The app uses Bluetooth low energy (LE) to estimate the distance and time between app users. It has been designed to make the best use of this technology.

Most of the time it will also give an accurate estimate of the distance between you and this other app user. No method of contact tracing is 100% perfect.


The app uses the Exposure Notification System (ENS) developed by Apple and Google. This allows phones to share anonymous IDs using Bluetooth. These IDs contain information about how close you were to another app user and how long you were close to them.

The anonymous IDs are codes made up of letters and numbers. You never see them. They cannot be used to identify users or their phones.

Using an anonymous ID means any information is collected anonymously. No one will ever know your personal details unless you choose to share them. This includes the MDHHS.

No one will know:

  • your name
  • who you met
  • what locations you were in
  • who tested positive for coronavirus

Read more about privacy and how we use your data


When you click on the SHARE A POSITIVE RESULT button in the app notify others tab you'll see 100% Transparency Checklist screen

On next screen Enter the PIN received from MDHHS or local health department

On next screen you can review and share your postive result

On next screen app will ask permission to share your device Random IDs

Allowing app to upload device Random IDs completes the process. MI COVID Alert mobile app notify others.


The app is part of our contact tracing operation. It uses Bluetooth and anonymous IDs to log:

  1. Download the free app from your usual app store.
  2. Choose what information you want to share, or not.
  3. Use your phone and other apps as normal - the app does its work in the background

You should be able to use the app if your phone:

  • is less than 5 years old
  • uses Apple's iOS 13.5 or higher or Google's Android 6.0 or higher


The app uses about 1MB of data per week. This is about the same amount of data you would use for 6 minutes browsing the internet.

Read about privacy and how we use your data


Using the app shouldn’t make a difference to your phone's battery life. The app uses Bluetooth Low Energy. This is the same technology used by smartwatches or wireless earphones. It's designed to be energy efficient.