The devices this is about allow to listen in remotely. I am pretty sure that even many of the wearers (children) don't know that. At least some of those devices

The devices this is about allow to listen in remotely. I am pretty sure that even many of the wearers (children) don't know that. At least some of those devices don't look like a smartwatch on first glance either, e.g. http://www.eltern-zeit.de/wp-content/uploads/lokato-kidswatch-gps-smart-watch-uhr-e1489949608512.jpg http://www.eltern-zeit.de/wp-content/uploads/lokato-kidswatc...