Follow and Follow me modes for Ardu Rover missing

At least Follow me mode should be available in ArduRover, regarding
FOLL_ENABLE : set to 1

Follow mode allow to add GPS NMEA data from serial port, but there is no way how to enable it.

In “Follow me” mode actually need to use Loiter mode with switched on GPS signal.
Tried to use iPhone as described without stable result.
Used settings: 115000, 2Hz
In iPhone application settings: GGA , RMC enabled
Any clues how to troubleshoot?