vfrTracker for iPhone/iPad is not compatible with iOS 11, a post will be added when the problem is resolved.

vfrTracker for iPhone/iPad is compatible with iOS 10.3.x Please see the installation instructions at Register iDevice, existing members delete the application and re-install vfrTracker from the link provided in the instructions. (GPS ERROR MESSAGE – delete the application and re-install vfrTracker)

vfrTracker for iPhone/iPad is compatible with iOS 10.2 Please see the installation instructions at Register iDevice, existing users delete the application and re-install vfrTracker from the link provided in the instructions.

vfrTracker compatibility with iOS 9.3.x :

Fully functional

After updating your iOS check vfrTracker GPS access;

1) iOS Settings
2) Privacy
3) tap Location Services
4) set to ON
5) scroll down to vfrTtracker
6) set to Never
7) and re-select While Using the App