Using Bluetooth Low Energy technology developed by Apple and Google COVIDWISE notifies users who have likely been exposed to reduce the risk of infection and help Virginia stop the spread. COVIDWISE does not rely on personal information or location data and participation is on a completely voluntary basis.
How It Works (Taken Directly from https://www.vdh.virginia.gov/covidwise/)
Download the free app from the iPhone App Store or Android Google Play Store.
Once you opt-in to the notification system, the Exposure Notifications System will generate an anonymous token for your device. To help ensure these anonymous tokens can't be used to identify you or your location, they change every 10-20 minutes.
Your phone and the phones around you will work in the background, without draining your battery or data, to exchange these privacy-preserving anonymous tokens via Bluetooth Low Energy (BLE) technology. This is a passive process that begins once you opt-in and functions without the app open.
On a daily basis, your phone downloads a list of all the anonymous tokens associated with positive COVID-19 cases and checks them against the list of anonymous tokens it has encountered in the last 14 days.
If there's a match, the app will notify you with further instructions from your public health authority on how to keep you and the people around you safe.
Learn more information here.