Andy Burns was thinking very hard :
newshound wrote:

[whatthreewords]

when I hit the "current location" button it drops the pin about half a
mile north of me.

This is on a desktop, with no GPS of course. OTOH Google Maps on the same
machine finds the right house.

On my laptop (similarly no GPS) the locate button pops up a permission
dialogue from the browser, if I say "yes" then W3W gets the correct position,
right down to the correct quarter of the house ... but the laptop and my
mobile are both signed-in on the same google account, and the phone has GPS
enabled (also WiFi triangulation works pretty well).

Seems to work extremely well on my Iphone, using its built in GPS, to
within yards. My Iphone seems to improve its GPS position data, over
the the first several seconds, so I'm guessing it uses an averaging
technique.

I recall once knocking on the door of a fire station, to advise them
that the field right in front of the fire station was on fire. With the
fire clearly visible over my shoulder, they wanted me to give them the
address of the fire.