During the update process, if the Control Hub detects that the digital signature of the APK that is being installed is different from the digital signature of the APK that is already installed, the Hub might prompt you to ask if it is OK to uninstall the current app and replace it with the new one.
This difference in digital signatures can occur, for example, if the previous version of the app was built and installed using Android Studio, but the newer app was downloaded from the GitHub repository.
Press OK to uninstall the old app and continue with the update process.