Thanks to GPS technology and many apps designed to work with that technology, it's possible to locate children using a cell phone with GPS capabilities as long as the child has that cell phone with them. For kids who don't carry these phones, other devices can be used.
Concerned parents can use GPS tracking to locate their phone-carrying children by installing and using one of the many location-based apps available for iPhones and Android devices. Parents install an app on their own phones as well, and they can see the location of their child's phone at any give time.
Life360 is a popular app designed to help parents track their children and children see where other members of the family are at any given time. All family members install the app on their phones and they can see the locations of the rest of the family on a map. This app is free, but the company offers a paid service with more features for families to use.
For children who don't carry phones, other devices work the same way. Some, like the Amber Alert GPS, let parents have two-way communication with their child as well, serving the same function as a cell phone.