Have you tried Homelink from the phone app when you are away from home and your car is still in the garage? Mine only works about 2 blocks away. You would think it would work from anywhere.
I'm fairly sure it is GPS dependant - i.e. you need to be near your home by design. I can see operating it far ways as a safety issue. You could close the door on someone or close the door on a car that's parked under the door. If you're nearby, you're more likely to know what is going on.