How To Access Device's Location Through Browser

In this blog post, I'll try to explore different mechanism to access device's location through the browser. By device, I mean laptops, PCs, smartphones and tablets. I'll try to present the tradeoffs of using different mechanism to learn device's location.

First using the HTML 5 geolocation api. This is a standard way of accessing the location powered by HTML 5. Almost every browser supports this capability. Moreover, returned location is more accurate if it's run by a device which has GPS capability such as a smartphone. To access location use the "navigator.getLocation.getCurrentPosition(showPosition)" method. You need to give a callback showPosition as a parameter. Once the location is known, callback will be called with position. Surprisingly this method is pretty successful in determining the device's location. Apparently, the high accuracy is due to the various information that the API uses such as the IP address, Access Point BSSID, Cell tower Id (if available) etc. Once such information is collected from the device, it's fed into a location service such as Google, Windows or Apple Location Services. Since these services are already mapped certain APs to locations, they usually return a good estimation of the device's accuracy. There is also watchPosition() and clearWatch() methods which enable continuous update of device's location. Finally, the only drawback of this method is that it asks user for permission as shown below. Hence, you might loose some privacy concerned people if you use this API.

Second method of learning the location is to use the IP address of the device and using a mapping service. Although it sounds simple, it requires a lot to learn device's location through the ip address. First, you need a server side script to learn the device's IP address as it's not possible to learn the external ip address in client side. Common way to learn the IP address is to have a server side script that returns back the IP address of an request. There are also some third party services which can do it for you. Once you have the IP address, second you need to map the IP address to geolocation. For that you need another third party service. Usually such services map IP to the scale of state successfully and if you're lucky maybe you get the city correct too. For me, it looks like a lot of dependency for such a basic functionality and the result would not be the around the accuracy that you might want. The only positive thing is, if you prefer this approach you won't get a browser popup for asking permission. If you're curious you can learn more about Internet geolocation from this paper.

Third option is not actually an option but it's something that I thought you can use. The idea is to use the BSSID of the AP that the device is connected. However, it looks like it's not possible to learn information about the AP using a client site scripting. So unfortunately, this is not an option.