Also, our Company is in the process of installing a feed from the Aircraft GPS (or perhaps FMC) position to the iPad for the same purpose. I think that connection will be via a USB charge port cable, although it could be Bluetooth - not sure. I haven’t seen one in service yet.
Blutooth through the IFE system.
At this time, the FAA does not allow own-ship display on portable devices while en-route.
I have always found this rule bizarre.