Thanks for reaching out to the Community space, @fmpy.
You can download the app to two phones in QuickBooks Self-Employed (QBSE). However, using it simultaneously is not recommended because it impacts the accuracy of the miles or trips.
For more information on how to use the QBSE mobile app to track your business miles, see this article: Automatically track mileage in QuickBooks Self-Employed.
In addition, you can add trips manually if you ever forget to take your device with you.
In case you encounter any issues when tracking mileage in the future, here are some articles you can check on what to do:
If you have further queries about tracking miles in QBSE, comment below. We're here to answer them for you. Have a wonderful day!
