A new smartphone app can help you learn if you have been exposed to someone who later tested positive for the virus that causes COVID-19.

Gov. Ralph Northam announced the app in a Richmond press conference Wednesday. He said Virginia is the first state to use the technology.

“We’ve said all along that our primary ways of fighting this virus include testing and contact tracing,” he said. “Today we’re launching a new way that we can all work together to help contain this pandemic. It’s a really powerful tool in our toolbox.”

The app is called “COVIDWISE.” Users install it on their phones, and the app recognizes other phones that have the app installed. People who have tested positive for the virus can voluntarily report their positive test on the app, and the app would then notify other users they may have been exposed.

Northam sought to allay privacy concerns during his press conference.

“I want to be clear, this app does not — I’m going to repeat that — does not track or store your personal information,” he said. “It does not track you at all. It doesn’t rely on GPS or your personal information.”

Northam said the app uses Apple and Google Bluetooth low-energy technology to assign random keys to positive cases. It uses those keys to determine if someone has been in close contact with someone who tested positive.

Northam also stressed that use of the app, including reporting a positive test, is voluntary.

“To repeat, you are in control,” he said. “All of this is your choice to download the free app and to use it, but I hope Virginians across the state will use this. This is another tool we can have to protect ourselves, our families and our communities.”

State Health Commissioner Dr. Norman Oliver said the state is not sharing data from the app with Apple, Google or Spring ML, the company that developed the app.

“This app doesn’t know who you are or where you are and will never know that,” he said.

Northam said the app will help people who get the alerts isolate themselves earlier, perhaps before they know they are sick.

“We know people are contagious before they show symptoms,” he said. “This can really help us catch new cases early before they spread as far.”

People can download the app on their smartphone on Google Play or the App Store.