Is it a bad idea to monitor small children that are prone to getting lost?
No, it's not a bad idea to monitor small children, in fact it's a really good one. But what's wrong with monitoring small children the old fashioned way? You know...actually watching them? Small children rarely get lost when they are properly supervised.
Because every once in a while, your attention may stray for more than 3 seconds, which is twice as long as it takes a kid to do something unexpected.
Paying attention to your kids isn't something that an app can replace, but an app can help.
I'm not trying to advocate people schluff off their parental responsibilities on an app.
For example, if the kids go to play outside, that's perfectly normal. Kids go to play outside so mom or dad can cook dinner or clean the house or whatever. And maybe the kids might even pay attention to you when you say "do go over there". But who knows? A stray cat may be around, and it might "go over there", and simply provide too much temptation for the kids to resist. That's not a matter of bad parenting - it's a matter of "shit happens" that you can't reasonably predict.
With a "virtual fence" built into an app where you could define geographical limits, you could get a warning that little Johnny has just hopped the fence and is heading towards the river where he saw the cat head off to. He's been told not to go near the river without you, but... would you rather be able to get a warning or not?
Or perhaps the pond nearby is frozen over, and you know that it only being -2 outside, it's just not safe to go out on. A virtual fence placed around the pond might be useful, because no matter how often you tell kids anything, something will happen, and you cannot supervise kids 100% of the time. You have to place a certain degree of trust in kids, and sometimes, that trust will be broken.
Who here has fallen through the ice before? On small ponds the ice can be a several inches thick at the edges, and get thinner out towards the middle. A thick bit of edge ice can be a great confidence builder, spurring you on to go further out onto the ice. Stamp your foot? Sure solid enough here. Go on a bit further out. But what did mom say about the pond? Nah... what does mom know? You can clearly see just how strong the ice is... A bit further... Which is all fine if the pond is only a couple feet deep... usually. But with larger ponds, lakes or rivers, you don't get the chance to make that mistake a second time.
Or do you chain your kids to a post in the basement because they'll be safe there?
It's all fine and dandy to talk about "good parenting" and "proper supervision" and have lofty ideals, but the reality is that no matter how hard you try, you'll never be able to live up to that 100% of the time. An app can help possibly catch a problematic situation when
(not if) your attention lapses.