On the leading edge of the trend is US-based Nextel Communications. The wireless provider began selling its Mobile Locator service last November, giving bosses an easy way to find employees who carry GPS-equipped mobile phones.
Earlier this month, mobile tracking firm Xora showed off the latest version of its Nextel GPS (global positioning system) phone software. The company says 1,600 corporate customers have signed up for its services, including "geofences" technology that sets off an alarm at the office when field workers go to pre-programmed off-limits sites, such as a bar or a park.
"There's no electro shock -- yet," Xora CEO Sanjay Shirole said.
Employee-tracking devices are gaining steam thanks to ever-more-accurate GPS technology and a US mandate requiring wireless companies to develop ways for emergency workers to find the physical location of people who dial 911 on a mobile phone.
Developed in the 1970s by the US military, GPS uses signals from low orbit satellites to triangulate the position of a ground-based receiver. GPS trackers were once an expensive luxury, but costs have plunged with the expansion of mobile phone services.
Now new enhanced 911 (E911) emergency regulations governing wireless carriers promise to unleash profitable new GPS services, analysts say. To comply with the rules, carriers have begun running more accurate GPS technology capable of supporting a range of commercial services that go beyond emergency location.
"This high-accuracy infrastructure is setting the stage for high-accuracy location-based services," said a spokesman for TruePosition, a mobile phone location service provider.
Other GPS mobile phone service providers include TeleNav and uLocate.
Tracking the market
In a sign of growing market for such services, GPS chip designer SiRF Technology, which provides GPS technology for handset maker Motorola, has seen its revenue grow from US$15 million in 2001 to $30.4 million in 2002 to $73.1 million last year. The company went public in April.



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