Let me start with mentioning that I’m writing this post on March 24, 2013. This kind of stuff is sure to change over time.
One of the things about the Internet is that it doesn’t have location built in. You don’t get to know where someone was when they wrote you an email, website operators don’t get to know where their visitors are when they visit the site. People don’t get to know where the craigslist servers are which put all those bytes together that make up a listing, and so on, and so on.
So people try to approximate. Because it is deemed to be useful information: country, region, city, latitude, longitude, ZIP code, time zone data and more. Even if it is not absolutely reliable, you can still derive some information, some picture. Different services are available, some free, some quite inexpensive, and some quite expensive. Most come in a form of a database file that you download, after paying for a license to use the data. Periodic updates to the database are made available. Web services are also available; this is where an IP address is submitted, over the Internet itself, to the service provider, and they immediately respond with their location data for this address. You can read more about IP Address Location at wikipedia.
Of course, these services don’t work when people use so called proxies and VPN‘s. In fact, proxies are set up precisely for the purpose of fooling services which are ordinarily restricted by location (e.g. for accessing Netflix or Spotify from non-US locations) into handing over the goods. Such proxies are not particularly costly to use.
Now, when you look at determining location for mobile devices, these models become quite questionable. Surely the network is not aligned with city boundaries, and surely a mobile device’s Internet address does not change smoothly as you move about. Of course, you can move faster than a database update.
So I thought I’d try out different IP Address location services – with my mobile device, using the “Data Plan,” not our home’s router or Wifi. I was in Vancouver, British Columbia, most definitely, the whole time.
|http://showip.net/||Vancouver, BC (this is said to be based on the free version of MaxMind, the paid version of which placed me in Toronto)|
|http://www.hostip.info/||“Location: … actually we haven’t a clue.”|
So, you see, some got it right, and some did not. (I didn’t even bother to read or record the latitude/longitude that were given in some cases.)