Understand how location tracking works. The Google library uses a Kalman filter with different location sources to estimate your true location using many sources all with a known error profile. Every source you add, even ones that are less accurate, help to reduce the aggregate error in your location estimate. It is a statistical calculation.
And yes, WiFi can give better accuracy than GPS:
Whenever you turn on Google Location services, a map of all WiFi hotspots is constantly being transmitted back to Google along with your calculated location using all available sources. Google stores all this information and over time generates a map of every WiFi hotspot throughout the world. Because of the huge number of samples they have from many different devices, they can geolocate a hotspot very precisely. With these hotspot location maps, they can triangulate anyone's position, often times more accurately than GPS.
Understand how location tracking works. The Google library uses a Kalman filter with different location sources to estimate your true location using many sources all with a known error profile. Every source you add, even ones that are less accurate, help to reduce the aggregate error in your location estimate. It is a statistical calculation.
And yes, WiFi can give better accuracy than GPS:
Whenever you turn on Google Location services, a map of all WiFi hotspots is constantly being transmitted back to Google along with your calculated location using all available sources. Google stores all this information and over time generates a map of every WiFi hotspot throughout the world. Because of the huge number of samples they have from many different devices, they can geolocate a hotspot very precisely. With these hotspot location maps, they can triangulate anyone's position, often times more accurately than GPS.