Watch or tracker?
A watch stays on the wrist, which is its main advantage, because it will not be left in a bag. Most add two-way calling to a short list of approved numbers, so a child can reach you without carrying a phone. A separate tracker is smaller and cheaper and suits a school bag or pocket, but is easier to forget.
Geofencing is the feature parents use most. Set an area around home or school and get an alert when your child arrives or leaves, without having to check the app. Check battery life too, anything under a full school day is impractical.
Related
For something worn on the wrist that a child can call from, see kids GPS watches. For an older relative instead, see GPS trackers for elderly.
Common questions
Can anyone call the watch? No. Only numbers you have added to the approved list.
Does it work at school? Yes, wherever there is mobile coverage. Some schools have their own policies on wearables, so it is worth checking.