This device tracked his movements 24 hours a day for four weeks.

They also install electronic devices to track or deter retail crime.

Under the right conditions, a highly sophisticated device may "see" the heat signatures of the people in a house and track their movements.

Neumann nodded, letting the President know their devices were tracking the call.

Olympic judges use a device to track who lands more scoring punches in a round.

Some ideas under discussion are technophilic, like global positioning devices to help fleets track their cabs.

The devices, worn on runners' wrists, track their elapsed distance, average per-mile pace and elevation.

Privacy can also be a problem when people use the devices to track the activities of a loved one.

The devices track locations using an analog cellular network system, and users find their property by getting real-time location data from a secure Internet site.

Acme can either sign an agreement to stop using the devices to track speeding, or fight the complaint in a hearing scheduled for Aug. 22.