I can see using it with younger children (having lost one or two along the line once or twice -- horrible feeling). But then again, I don't give my children cell phones, so that is sort of a moot point. I can see using it on an older kid if they were causing trust issues, but then again, I probably wouldn't let them have a cell phone at that point and they would be under my nose at all times until they re-earned that trust. Again, not a problem I have ever had with any of my kids, so this is all supposition on my part. As a teacher, you'd be surprised (or maybe you wouldn't) at what kids are doing while their parents aren't looking. Scary, scary. So glad I had pretty good kids.