Introduction
In this article I will explain how to access the current user's details. We can get userip, usercountry, usercity, userregion, userlatitude, userlongitude and usertimezone about the user. The "smart-ip.net" JSON string is used to access all the information about the user. 
Complete Program 
User_Infromation.html
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title></title>
    <script src="jquery-1.8.2.js"></script>
    
 <script type="text/javascript">
     var userip, usercountry, usercity, userregion, userlatitude, userlongitude, usertimezone
     function UserInfo(data)
     {
         userip = data.host;
         usercountry = data.countryName;
         usercity = data.city;
         userregion = data.region;
         userlatitude = data.latitude;
         userlongitude = data.longitude;
         usertimezone = data.timezone;
     }
     $(function ()
     {
         UserInfoDetail();
     })
     function UserInfoDetail() {
         document.getElementById('userip').innerHTML = userip;
         document.getElementById('city').innerHTML = usercity;
         document.getElementById('country').innerHTML = usercountry;
         
         document.getElementById('region').innerHTML = userregion;
         document.getElementById('timezone').innerHTML = usertimezone;
        
         document.getElementById('longitude').innerHTML = userlongitude;
         document.getElementById('latitude').innerHTML = userlatitude;
         
     }
</script>
    <script type="text/javascript" src="http://smart-ip.net/geoip-json?callback=UserInfo"></script>
</head>
<body>
<div>
<table id="Details" cellpadding="2" cellspacing="2" style=" border:1px solid #000; font-family:'Segoe UI';" >
<tr style="background-color:#666666; color:White; font-weight:bold">
<td colspan="2" align="center">Current User Details in JavaScript</td>
</tr>
<tr style="border:solid 1px #000000">
<td align="left"><b>IP Address  :</b></td>
<td><label id="userip"/></td>
</tr>
 <tr>
<td align="left"><b>City  :</b></td>
<td><label id="city"/></td>
</tr>
<tr>
<td align="left"><b>Country  :</b></td>
<td><label id="country"/></td>
</tr>
<tr>
<td align="left"><b>Region  :</b></td>
<td><label id="region"/></td>
</tr>
<tr>
<td align="left"><b>Time Zone  :</b></td>
<td><label id="timezone"/></td>
</tr>
<tr>
<td align="left"><b>Longitude  :</b></td>
<td><label id="longitude"/></td>
</tr>
<tr>
<td align="left"><b>latitude  :</b></td>
<td><label id="latitude"/></td>
</tr>
</table>
</div>
</body>
</html>
 
Output  
  
![Output.jpg]()
For more information, download the attached sample application.