Advertisment

Adding Geo-Location to Your Apps

author-image
PCQ Bureau
New Update

You must have wished for a  'guide'  that can live in your pocket everytime

and assist you where ever you go? Be it a new city or a country you would love

to get information related to nearby motels, restaurants, pubs and disco from

this 'guide'.

Advertisment

The good news is it is possible to have one. The Geolocation API used with

your smartphone helps you achieve it. Smart devices like iPhones, Android, etc

have such applications available which detect your current position and provide

you with the information related to your location.

What is geolocation?



Location to a person means context and context means 'higher relevance.'

Location can be represented in different forms. It can be your longitudinal and

latitudinal value, city & state name, street address or a nearby address.

There are many business search APIs present on the web today. To name a few:

Yahoo Local Search API, Yelp API, Localeze, etc. These business APIs help a

small business to grow by providing useful data. Small businesses are tough

since their databases are not complete. With growing APIs and supporting scripts

available on the Internet, web is changing. A lot of companies are adopting

location detection APIs and the change is there for all to see. Google, Firefox,

Opera have already jumped onto it. With Firefox, Safari and few others

supporting location awareness, the day isn't far when other browsers shall do

the same.

Advertisment

Direct Hit!

Applies To: Content developers



USP: Know your visitors by location, and serve them relevant
content Primary Link: www.w3.org/TR/geolocation-API Search

Engine Keywordes:
geolocation, location awareness, map

Sources for detecting geolocation



There are two primary methods of detecting current location of a device:

1.         IP geolocation



2.         Triangulation

Advertisment
  • GPS

  • Wi-Fi

  • Cell Ids (depending upon the service provider)

1. IP Geolocation



In this method, the IP address of the hosting device is used to detect the

current location. This is the easiest method to detect the current location and

is widely available. This method does not require  special technology like

Bluetooth, GPS etc.  in the hosting device. However, it is accurate only till

the city level and not below.

2. Triangulation



This is done using the following techniques:

Advertisment
  • GPS (Global Positioning System) has a coverage radius

    accuracy of 10 m and is highly accurate in open areas. However it does not

    work well in congested areas or indoors. It takes a lot of time to detect

    satellites but works well after it gets a fix. The mobile technology is pretty

    useful for maps and helps in road navigation.

  • Wi-Fi is yet another source of location detection and is

    highly accurate. Its fix time is lesser as compared to GPS. It has a coverage

    radius of 20m, but does not work well in rural areas or where there's no Wi-Fi

    enabled.

  • Cell Ids is the method to detect current location via

    cellular radio. It is not an accurate method to detect location but is widely

    available where there is cellular coverage. It does not take much time for

    first fix and does not require special hardware to detect current location.

The location detected by above methodologies is approximate

and not very accurate. Various companies are working on such kinds of

interactive applications which respond to the user just like a human.

By embedding the geolocation API, within a website you can

search for the precise location of a person or place.
Advertisment

Getting precise information



This is possible by making all future browsers compatible with an API for

retrieving geographic position information associated with a hosting device. The

geographic position information is provided in terms of world geodetic system

co- ordinates. The API provides latitudinal and longitudinal coordinates which

can be used to get city and state information by doing a reverse lookup. If you

are using Mozilla Firefox and you have JavaScript enabled then by using the

following snippet of code you can quickly get your current coordinates. To do

so, create a blank HTML file and paste the following javascript code. The

browser will then ask if you want to share your location or not. If you allow

the browser to share location you will see the current latitude and longitude.





Know your current location



Security issues



Since all future browsers plan to use the API for location awareness of

users, this may lead to privacy concerns. To protect user's privacy an

application must ask a user before sharing his/her location. The API defined in

this specification can be used to retrieve the geographic location of a hosting

device. This can also lead to many security exploits; hence a mechanism should

ensure that no location information is made available without the user's

permission.

Advertisment

Benefits



Someone visiting a foreign city could access a Web application that allows

users to search or browse through a database of tourist attractions. Using the

geolocation API, the Web application has access to a user's approximate position

and is therefore able to rank the search results by proximity to a user's

location. A tour-guide Web application can use the Geolocation API to monitor

the user's position and trigger visual or audio notifications when interesting

places are in the vicinity. An online task management system can trigger

reminders when the user is in the proximity of landmarks that are associated

with certain tasks. A widget-like Web application that shows the weather or news

that are relevant to the user's current area can use the Geolocation API to

register for location updates. If the user's position changes, the widget can

adapt the content accordingly.

Social networking applications



A social network application allows its users to automatically tag their

status updates with location information. It does this by monitoring the user's

position with the Geolocation API. Each user can control the granularity of the

location information (e.g. city or neighbourhood level) that is shared with

other users. A user can also track his network of friends and get real-time

updates about their current location.

XHTML 1.0 Strict//EN"



"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">











Google Maps JavaScript API Example: Map Markers   













Advertisment






It is worth noting that latitude and longitude detection

via IP address depends upon your ISP and other supporting factors, it may or may

not be accurate.

Sachin Khosla, Digimantra

Advertisment