Verizon is getting ready to launch a new GPS child tracking service called Verizon Chaperone. The new service is anticipated to be available in May, powered by the LG Migo phone. It is anticipated the service will cost $15 per month.
Among the features of this location based service (LBS) are geofencing; the process of setting up a perimeter something is able to travel before an alert is setup. In this case you can setup a geofence around a few city blocks, a city, etc and then parents will automatically receive a text message if the child travels outside that geofence.
Other location based services are in the works for Verizon in the next few months in addition to the previously discussed Verizon VZ Navigator service which provides driving directions over cellphone.