Dogtra Pathfinder GPS Collars

from my understanding, which is limited at the moment is that it does not need a phone signal, just the phones GPS capability. There is an app which links to the GPS, collar unit and receiver. I am awaiting an update from Dogtra Europe, they are often slow in bringing out European variants but the key thing is that they have to be in a position to provide repairs and warranty support for the models hey stock and that I subsequently stock.