Focus by TeenDrive requires that the driver's iPhone has a recent version of the iPhone Operating System (iOS) installed. The minimum supported version is iOS 10. If your driver's phone has an older version you'll need to update it.
Follow these steps on your driver's phone to update it to the latest version of iOS.
1. Find and open the Settings app on your driver's phone
2. Tap the "General" row
3. Tap the "Software Update" row
4. Tap "Install Now" and follow the instructions on the phone to update iOS.
5. Once the update is complete, the driver's phone will restart and you can return to the Focus by TeenDrive iPhone Setup Tool on your computer to continue setup.