that said, when using worldalignment gravityAndHeading, any location inaccuracy when the ARSCNView starts up will throw off the AR illusion, sometimes considerably. I hope apps will be able to correct during an ARSession when better location data is detected
there is no iBeacon (not sure where you're quoting that from?), its just spatial data (lat/lons) projected into the SCNScene coordinate space (which is relative to the location and heading of the device when the ARSession starts)
ok yes, an iBeacon is one possible way CoreLocation determines a device's location. in this case there was none, only GPS (and I guess Wifi is used as well)
I think the way GPS apps have resolved this is using your bearing, comparing it to lanes on the road, and moving the route to match where you are actually moving. This might need some finer adjustment based on where your camera is pointing and your bearing.
https://twitter.com/bFlood/status/888485889248157697
that said, when using worldalignment gravityAndHeading, any location inaccuracy when the ARSCNView starts up will throw off the AR illusion, sometimes considerably. I hope apps will be able to correct during an ARSession when better location data is detected