Without user self-reporting, beacons or other supplemental location technology, a mobile device location is only accurate to within about 93 feet, a study has found.
Conducted by PlaceIQ -- a US-based company that builds mobile audiences and analytics from location intelligence for digital advertising -- in collaboration with independent firm called Findyr, the report demystifies mobile location and identify "ground truth" regarding device location accuracy.
Findyr sent people in five US cites to 150 specific locations and asked them to record their latitude/longitude coordinates within the Findyr app on their phone.
The participants also sent a photo or video of where they were standing to verify their actual physical location.
"Location accuracy was reflected as the difference between recorded user location versus actual user location. Accuracy varied in each of the five cities, but, as indicated, average location accuracy across the five markets was 93 feet or 30 meters," the report said.
The five cites tested and their accuracy were Boston -- 69 feet, New York -- 75 feet, Washington -- 76 feet, Chicago -- 87 feet and Austin (Texas) -- 91 feet.
PlaceIQ explained that Austin location accuracy was worse than other cities because it was less dense and, thus, probably had fewer WiFi hotspots, though GPS may be more accurate in Austin than in a more heavily developed urban environment.