The Litchi app has no range limitation from a practical point of view, because it will allow you to program missions far beyond the capability of your battery. I have programmed some missions that were so long that they automatically aborted mid-mission. A Low Battery RTH will be activated (assuming you are already far beyond RC range and you cannot cancel the RTH). Note that this Low Battery RTH point is dependent on distance from home. I've had a Low Battery RTH kick in when I had as much as 60% battery still available, because it needed all that 60% to get home with the specified reserve. Be careful to keep a reasonable reserve to allow RTH against headwinds if necessary.