Geospatial Semantic Web Blog

A question that most parents with teenage children often ask is “where are you?”. To help to answer this question, wireless service providers begin to offer location-based services that allow parents to monitor the whereabouts of their children on home computers.

To determine the location of a cellphone user, a service makes use of wireless signals from the cellphone. Based on the cellphone’ signal strength, the service is able to compute the relative position of the user from a group of cell towers. Knowing the geographical location of the user’s cellphone (i.e., a latitude/longitude value pair), the service then perform “reverse geocoding” to determine the location of the user.

In theory, the service works. In practice, however, there is a problem that was quite unexpected. Here is the problem:
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Blutooth MediaServer is a location-based system that distributes advertising via Bluetooth. Access Points of the Bluetooth MediaServer are typically placed in high-traffic locations such as restaurants, movie theaters and shopping malls. Upon entering the vicinity of these Access Points, customers who carry active Bluetooth devices (e.g., cellphones and PDA) will automatically receive targeted advertising messages.

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On the way home yesterday I was thinking about useful location-based services (LBS). In particular, I was imagining the kind of LBS that would be useful to the everyday mobile phone users.

Here is a list of imaginary LBS that came to my mind:
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