The U.S. Food and Drug Administration issued a warning this past week about the effect that magnets in some cell phones and smartwatches can have on pacemakers and other implanted medical devices.

A pacemaker, which unconfirmed media reports say Nancy Guthrie has, does not contain GPS and cannot be used to track a person's location. A pacemaker will continue to function even if it stops syncing ...

Data from Nancy Guthrie's pacemaker has helped shed light on the events leading up to her kidnapping, but there are significant limits in how much data the devices can collect. Most importantly for ...