We're all getting used to having good-quality turn-by-turn navigation available to us as we travel, but it still seems all to easy to get lost - or at least to get frustrated finding what you are looking for - in large indoor spaces. Google Maps for the Android mobile operating system pioneered indoor navigation, giving you accurate building interior maps and blue-dot personal location within airports, major transportation hubs, and big-city retailers in many parts of the world.
But indoor navigation is quickly evolving into something much more than "here you are" positioning. Mobile app makers have begun to build turn-by-turn directions and additional information into the indoor navigation experience. Meridian Apps, for example, has worked with Macy's department store to push "indoor GPS" to new levels of functionality. The latest version of the Macy's app includes a map of all 11 levels of Macy's Herald Square store in New York City. But that's just the start. "Use the search tool or tap on the 'map' feature to discover departments, brands and other points of interest," states Meridian. "These points of interest on the map will have 'Take Me Here' buttons that can be tapped for receiving turn-by-turn directions."
Other organizations tapping Meridian's indoor GPS tools are the American Museum of Natural History, the Miami Children's Hospital, and the Venetian Hotel in Las Vegas.
There are significant advantages for organizations using proprietary indoor navigation apps, rather than Google-powered maps. Macy's, for example, Integrates store hours and other details, an event calendar, restaurant locations and details, and offers into its app. A proprietary app also provides the owner with the opportunity to promote special offers specific to the area of the store where the customer is located.
How 'Indoor GPS' Works
So-called indoor GPS isn't GPS at all. In the case of both Google's offerings and those by Meridian, the indoor location apps operate by determining position based on internal signals. The actual GPS satellite signal is too weak to penetrate larger buildings, and couldn't do the job. Instead, the apps use a number of WiFi stations positioned around a facility to let the user's smartphone determine location by triangulation. Equipping an indoor location with full-facility WiFi also enables the app owner to send push notifications and other data to app users.
In the case of Google Maps for Android, "Detailed floor plans automatically appear when you’re viewing the map and zoomed in on a building where indoor map data is available," states Google. "The familiar blue dot icon indicates your location within several meters, and when you move up or down a level in a building with multiple floors, the interface will automatically update to display which floor you’re on. All this is achieved by using an approach similar to that of ‘My Location’ for outdoor spaces, but fine tuned for indoors."
Other apps offering indoor WiFi positioning include Wifarer, and Navizon. Navizon's Indoor Tracking System (ITS) helps mobile device users accurately determine location indoors with the help of purpose-built WiFi nodes placed within buildings. App-makers may also use Navizon's capability to enable real-time friend tracking (mutually opted in), and surveillance in high-security settings.
Indoor position tracking techniques vary, but for the most part, they rely on triangulation from known fixed points, usually WiFi nodes. Webster's defines triangulation as a "trigonometric operation for finding a position or location by means of bearings from two fixed points a known distance apart," and that's pretty much how the positioning systems operate.
The benefits of indoor tracking, such as knowing your location in a building, turn-by-turn directions to a searched destination, special offers depending on your location, and "find-a-friend," come at a cost to privacy, and everyone involved, including the organizations offering this service, individuals, and government, will need to monitor and make sure strong opt-in and opt-out choices are available to the public.