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How Spy Gear Works

Tracking Devices
GPS units and other common tracking technologies have made it easier to perform surveillance on others.
GPS units and other common tracking technologies have made it easier to perform surveillance on others.
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­There's no question about it -- Global Positioning System, or GPS, units have made life for many of us a lot easier. Anyone who has a tough time just getting to the grocery store and back probably welcomes the rise in popularity of GPS units. Most models provide simple yet precise information on how to get from point A to point B with good accuracy -- by sending and receiving information to and from a network of satellites, a GPS unit can calculate its precise location, along with important factors like speed and direction.

As companies producing GPS devices add the Internet and other novel features to their products, the technology is becoming more and more convenient for drivers. And it's not just typical GPS devices that help us get around. Many smartphones now have GPS capability (albeit with an extra monthly fee). It's even possible to download location tracking applications onto iPhones and phones running Google's Android operating system.

But the nature of sophisticated tracking technologies, like GPS devices, has also made it easier to use them as surveillance devices to track people's location -- for better or for worse. Law enforcement officials have used GPS and other tracking technologies, including radio frequency (RF) technology and radio frequency identification (RFID) technology, to track criminals for several years. By placing a tracking device onto vehicles, police have been able to track and catch suspects after strings of theft, assault or other criminal acts [source: Hubbard].

As with most surveillance equipment, the legality of using a tracking device for personal use is shaky. Although most judges have allowed law enforcement officials to use GPS devices during investigations to catch criminals, the matter becomes different when one citizen uses a tracking device on another. Just like rules concerning video and audio surveillance, fitting someone with a tracking device without his knowledge or permission is illegal, and a person should apply for a warrant if there's any concern over illegal activity.

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