You can bookmark the Companion App in your mobile device's (smartphone or tablet) browser so you won’t have to scan the QR code each time you want to use the companion app. Click on three dots on the top right screen, then click on Add to the Home screen. The Companion App will appear in the next available space on your phone's Home Screen.
The Companion App is a webpage and not a standard downloadable app. This is so there is as little lag as possible and when you change lanes or deploy a super it is seen in game real time.