3.14  Location-Based Services

Location-Based Services (LBS) are applications that take your geographic location (city, state, location of your mobile device, etc.) into consideration. While the term generally refers to services accessed on mobile devices using the Global Positioning System (GPS), it can also be used to describe web applications that take your location into account. Search engines including Yahoo! Local and Google Maps use localization to provide you with geographically relevant content. Local search is particularly useful when you want to find a nearby business (e.g., plumbers, taxis, etc.). Location-based services are becoming increasingly popular in Web 2.0 applications. Conferences related to LBS include O’Reilly’sWhere 2.0 and the Location Intelligence Conference.

Global Positioning System (GPS)

The Global Positioning System (GPS), developed by the United States Department of Defense, uses numerous satellites that send signals to a GPS receiver to determine its exact location. (A Russian system called GLONASS also exists, and a new system named Galileo is under development in Europe.) In the 1980s, the US Department of Defense opened GPS for civilian use to encourage satellite technology development.¹ Numerous location-based services are now available using GPS technology, such as GPS mapping devices used in cars or on mobile devices. GPS is also being used for safety. The US Federal Communications Commission (FCC) now requires wireless carriers to provide the locations of wireless customers calling 911 so emergency services can find them faster. To meet this requirement, wireless carriers have developed GPS-enabled cell phones.² These phones also provide premium services, such as driving directions and local information. The Disney Family Locator service uses GPS-enabled phones to help parents keep track of their children (as long as the child is carrying the special cell phone).³

Mapping Services

Google Maps is one of the most popular mapping applications available online. You can use Google Maps to locate businesses in your area, get driving directions and live traffic information, create custom maps with images and more. You can even get the information by using your mobile device. Google’slocal search allows you to locate a business in a geographic area and get its address, phone number, driving directions and even user reviews. Google Earth provides satellite images of virtually any location on the planet. In some areas, you can even get a panoramic view of a neighborhood at street level. You can use the Google Maps API to add mapping capabilities to your websites and web applications.

MapQuest, owned by AOL, provides similar mapping services. Use it to get directions and maps on your desktop or mobile device. The MapQuest OpenAPI allows you to add location-based services to your web applications. Additional mapping services include Yahoo! Local Maps and MSN Live Search. Both services offer maps, driving directions, traffic information and local search.

Companies such as NAVTEQ andTele Atlas provide digital map data for in-vehicle and portable navigation devices, websites, location-based services and more. Developers building commercial location-based services can license the robust mapping products from these companies to build richly functional web applications.

GeoRSS and Geotagging

GeoRSS, based on the RSS standards, is a set of standards for representing geographical information in a feed. Location and geographical information in a GeoRSS feed can be used in GPS devices, mapping applications and other location-based services. For example, a blog post about a vacation could map the locations mentioned.⁴

Geotagging can be used to add location information (longitude, latitude, etc.) to websites, images, RSS feeds, videos and more. Websites can often determine a user’s location by their IP address. Geotagging a website provides the user with location information about the site.⁵ Geographic information can be used to add value to search results. Geotagging could also be mashed up with existing visualization systems, such as Google Earth or MSN Virtual Earth, which provide advanced satellite images for anywhere on the planet.

1. Schiller, J. and A. Voisard. Location-Based Services. Morgan Kaufmann, 2004.
2. Malykhina, E. “Nokia Wants Your Cell Phone To Tell You Where You Are.” InformationWeek, 9 Oc- tober 2006 <http://www.informationweek.com/showArticle.jhtml?articleID=193105219>.
3. Magid, L. “Global Positioning by Cellphone.”New York Times, 19 July 2007, C7.
4. “GeoRSS: Geographically Encoded Objects for RSS Feeds.” GeoRSS <http://georss.org/>.
5. Turner, A. “Geotagging Web Pages and RSS Feeds.” Linux Journal, 11 January 2005 <http://in teractive.linuxjournal.com/node/8025>.