I may be getting confused but I pretty sure, when you connect an Iphone to and IPad using the personal hotspot, the IPad will be able to use the GPS from the Iphone when using the Garmin Blue Chart App. If I start the Blue Chart App without the IPhone connected, I get no location for the vessel (the boat icon is not on the screen). When I connect the Iphone, the vessel icon shows up on the screen at the correct location. I can't say for sure it is the GPS position but it sure seems like it. I need to get out of cellular range to be sure.