GPS Mobile. GPS/GPRS device combines GPS tracking, a geo-fence (leaving the area triggers an SMS alert) and SOS alerting functions for protecting the young and elderly in one neat package. It also sends you an SMS of the last location if the device is taken underground or loses signal in some other way, and it has a speeding function to send an alert if your kids are racing the lawn mower again.
block it with a gps jammer
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