Some anti-GPS tracking devices include GPS jamming gadgets, metal shields, GPS spoofing gadgets and mobile phone jammers. These items either block or scramble the signal from the GPS, which means individuals cannot read the location of a GPS device.
GPS jamming gadgets are available online, and the most popular models plug into a car's 12-volt adapter. These interfere with the GPS radio signal at a range of approximately 30 feet. A metal shield is another option for stopping GPS signals, and this is a cheap option that does not require power. Metal may work well to block GPS as car thieves often transport stolen vehicles with GPS in metal trucks, so the signal is not available for tracking.
There are also GPS spoofing gadgets available, and these send a fake signal out that overrides the signal that comes from the regular GPS device. These report a fake location, though they can be dangerous, as they may affect other GPS devices, too. There are also mobile phone jammers that can block the transmission of GPS location devices since these use a wireless carrier to send this information. If the mobile phone jammer is blocking the wireless connection, the GPS information cannot travel. Though these jammers do work to stop GPS location transmissions, they also block any mobile phone signal.