use a phone with GPS to post an online message revealing their location.
The signals that a GPS receiver or Sat Nav system uses to calculate its position are broadcast freely and globally by the GPS satellites orbiting earth 20,000Kms away. As there is no way for the GPS satellites to know who or what is receiving or using the signals that they broadcast, it would be impossible to charge people for their use. Much like free to air TV or radio. Subsequently, the GPS service is free. The hardware required to use it however will cost you.
The signal for GPS systems originates from satellites that orbit above the earth. This means that the "signal" that is used for GPS tracking is pretty much everywhere, and therefore cannot be "homed" in on using standard radio location techniques. The GPS tracking unit is therefore a receiver of signal, not a transmitter like an audio "bug" or wireless video camera. Locating a GPS "tracking device" is probably possible using advanced equipment that would not be readily accessible to most people. This would also mean that said equipment would not be "inexpensive", either.
the navy
Yes it would. Global is worldwide.
The Overshare - 2009 was released on: USA: January 2009
Overshare 3D - 2010 was released on: USA: 1 October 2010 (Project Twenty1)
The cast of The Overshare - 2009 includes: Nicole Gerth as Woman in wheelchair Jake Olson as Jake
The cast of Overshare 3D - 2010 includes: Mark Beacraft as Vice Principal Gitz Lilliana Guinto as Nikki
About % of the people with the Smartphones use the GPS.
All kind of people can use the GPS. Sailors,people on the streets, and truck drivers. So There are different people who put GPS to Use.
A bluetooth GPS will cost on average at least $25-50 more than a regular GPS. A good alternative would be to get the GPS capability via a smartphone.
Yes it would, it might be a little less detailed than a normal GPS but it still is one. The cellphone's GPS will show roads and direction, like a compass.
Not all phones have GPS. And not all phones that have GPS have activated GPS upon first use. For many, you would have to enable the GPS first.
Any GPS would be good for geo caching. Now you can rent one from libraries just for geo caching so you don't have to pay for one. A lot of people use the GPS on their smartphones.
I would not recommend buying a Polar GPS watch as an alternative to your typical GPS systems. While the Polar GPS is accurate for runners it is not accurate enough for a vehicle.
Almost 17% of Americans own a GPS device, whether in their car or on their phone or other wise. An approximate number would be around 3,065,849 people, and the number continues to climb. (Maty 2013)