The State of LBS in the US at Wap Review: "For a long time mobile visionaries have been heralding the imminent arrival of Location Based Services (LBS), and the revolutionary mobile applications and services that they will make possible.

Since the beginning of this year, US cellular operators have been legally required under the provisions of E911-Phase II to furnish real time geolocation data to emergency agencies when users call 911, the nation-wide emergency telephone number. The requirements specify that the systems be able to locate the user with an accuracy of 125 meters at least 67% of the time and 300 meters 95% of the time. This means that your cellular network probably knows where you are. While this has serious privacy implications, it also has the potential for the development of powerful new mobile services. LBS can enhance many types of mobile applications. News, weather, maps, directions, local search and even dating services are all much more attractive when they provide location relevant information without the user needing to key their location information into the phone.

The carriers chose to implement E911 using two very different technologies. The major CDMA carriers, Verizon and Sprint, along with iDEN based Nextel, use phones with built in GPS receivers. Cingular and T-Mobile, the dominant GSM carriers, implemented E911 using a network based solution involving triangulation and timing to ca"