A Tracing program

[vedisn]

I need some help please. I want to develop an application that can track somebody's movement with the help of a mobile phone that is possessed by the person being tracked. I should be able to see an icon moving on a map as the person moves from place to place, am aiming to see the icon moving in Google earth with respect the persons current position. My problem is that am not sure of the technologies to use to enable me develop this application and how will the phone and the computer program communicate so as to update the icon on the map as the person moves. Please somebody help me to find out the requirements needed to implement this application and how I can go about implementing this application.

[Norm]

To get the persons location, do you need a GPS?