We gave the 10.3.6 version of Collector for ArcGIS (Windows beta) a try on a Panasonic Toughpad FZ-G1 that is running Windows 10. The Toughpad model we used includes a built-in GPS receiver, however, we could not get it to play well with Collector.
Collector seems to be using the Windows Locator service for position information. So I'm not sure if this is an issue with Collector, the Windows Locator service, or the Panasonic driver for the built-in GPS. ArcMap, which connects to the GPS as a serial device, works just fine on the same computer.
When the Toughpad is connected to the network, Collector displays a location for several seconds that appears to be coming from the Wifi with very poor stated accuracy. It will then jump to a different location for a second or two that appears to be from the internal GPS receiver with the expect accuracy. It then goes back to the other location, and repeatably jumps back and forth between the two.
When the Toughpad is completely off the network, wired or wireless, the only location it seems to display is the last position from the last network to which it was connected.
Anyone have any suggestions for getting Collector and the built-in GPS on the Toughpad FZ-G1 to play well together? Is this a bug in Collector, or somewhere else in the chain? Is the GPS in our setup an "external" one from the perspective of Collector, and, hence, currently unsupported until you finish support for external GPS receivers?