Wi-Fi Positioning System (WPS) is a term pioneered by Skyhook Wireless to describe its Wi-Fi-based location system. Skyhook has built and maintains a large global database of Wi-Fi access points and their precise locations. This data may then be used by a mobile electronic device to triangulate a user's position.
WPS may be combined with cell phone tower triangulation and GPS to provide reliable and accurate position data under a wide range of conditions, including among tall buildings and indoors, when GPS signals may be weak or intermittent.
Limitations: WPS does not work when out of range of Wi-Fi signals, and the Wi-Fi hotspots database must be constantly updated to keep up with Wi-Fi hotspot changes.See also fake gps.

