My phone has GPS, so???

continuation from my last article "Use technology"

GPS stands for Global Positioning System. It is used to know your exact location on the face of earth. I'm sure you have seen this technology being used in Hollywood movies. From a hand held GPS device one can see where he exactly his on a pre-loaded map. And in movies everyone has a GPS device and the whole army knows where their comrades are! To some this seems like high end technology, but it's not. By the end of this article you will know how to assemble your own army with hand held GPS devices without spending a dime.

Lot of Sri Lankans think that GPS is not available in Sri Lanka. Another common belief among Sri Lankans are that GPS is a service that you have to pay monthly to obtain. Let me enlighten you by starting out with the history of GPS.
GPS technology developed and first used by the American military. They launched satellites that orbit above earth which sends necessary signals to calculate positioning information so precise one could measure centimeters with their GPS device. These signals were encoded and only the US military could use it. Now they have let civilians use the technology but with much lower accuracy. That is what people all around the world use as GPS.

The theory is very simple. US military owned satellites emit certain signals every pre-defined interval continuously. GPS devices capture these signals. These signals are encoded with information needed for the GPS device to calculate distance from that particular satellite. After recieving such signals from 3 satellites (distances from 3 known points) the position of the GPS device can be calculated easily by the GPS device. (Intersection of 3 spheres are two points, one point is not on the face of the earth! So other point is where the GPS device is... pretty simple) more...

US satellites provie this service free of charge for civillians because it is not much of a security threat and bases GPS navigation technology which is essential mostly for ships and boats.

Sri Lankans who don't believe in GPS,

Most of the high end mobile phones have GPS devices built in. If your phone has that feature that means you can find your exact location on earth. (Even in Sri Lanka ;)) So find that option on your phone. It will say "searching for satellites", "calculating GPS data" or something equivalent to that. Go out to a place where your phone can see the sky. Wait for about 5 minutes. Then it will show you the latitude and longitude of your current position. This doesn't cost you anything.

And now let me tell you about Google Maps Mobile. I'm sure you all know about google earth. This is the mobile version of that. Since you have your current location from the in-built GPS device now you can see where on earth you are with this software installed on your mobile phone. Google recently introduced a feature called Google Latitude where you can see the position of your friends as well. Make your friends who has GPS enabled mobile phones your comrades and you've got a "high tech" army. ;)

GPS devices on mobile phones are far less accurate than regular GPS devices. To use a regular GPS device in Sri Lanka one needs a permission from the authorities due to security reasons.

In Sri Lanka there's no highly detailed map as yet. So options like routing and voice navigation doesn't work. When you are seriously lost in Colombo and need to find a way out, you will praise Google Maps Mobile for atleast showing you where you are!