Abbreviation for Global Positioning System; a navigational system using satellite signals to fix the location of a radio receiver on or above the earth's surface. Also "GPS" refers to the radio receiver used to receive GPS signals.
Global Positioning System (GPS) is a space-based global navigation satellite system (GNSS) that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites.
It is freely accessible to anybody with a GPS receiver. Apple, Google, and other mobile providers have developed frameworks to deal with the location services calculated from GPS, WiFi or Cell Tower.
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