Unable to add contacts via Bluetooth with Android 6
Apparently, you need the ACCESS_COARSE_LOCATION permission to use Bluetooth on Android 6. So we need to ask the user to grant this permission before contacts can be added via Bluetooth.
To quote from the issue report:
To access the hardware identifiers of nearby external devices via Bluetooth and Wi-Fi scans, your app must now have the
ACCESS_FINE_LOCATIONorACCESS_COARSE_LOCATIONpermissions
This is a sub-issue of #158 (closed).