HTML5 Geolocation API

Lowest Supported Browsers

IE 9.0+, Firefox 3.5+, Chrome 5.0+, Safari 5.0+, Opera 10.6+, iOS Safari 3.2+, Opera Mobile 11.0+, and Android/Browser 2.1+/3.0+
For current compatibility see here http://caniuse.com/geolocation

Geolocation API Specification

http://dev.w3.org/geo/api/spec-source.html

Technology Used

Global Position System GPS
Assisted GPS (A-GPS) cell site triangulation

Example JavaScript

 //Check if browser supports W3C Geolocation API  
 if (navigator.geolocation) {  
   // single shot position request (others are repeat + cached)   
   navigator.geolocation.getCurrentPosition(successFunction, errorFunction);  
 }  
 else {  
   alert('Geolocation API is not supported by your browser.');  
 }  
 function successFunction(position) {  
   var lat = position.coords.latitude;  
   var long = position.coords.longitude;  
   alert('Your location coordinates are: Latitude:'+lat+' Longitude: '+long);  
 }  
 function errorFunction(position) {  
   alert('Error!');  
 }  

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