GPS receivers collect signals from navigation satellites in orbit. The signals are available at all locations on Earth, and anyone can use them free of charge. GPS receivers come in a wide variety of models for various professional and recreational uses. Whether a GPS is worn on the wrist, is handheld, is installed in a vehicle or is mounted on a tripod, its accuracy determines its grade. The most accurate GPS is called “survey grade.” Writer Bio

The Difference Between Handheld GPS Receivers   Surveying Grade GPS Receivers - 96