What's a good Android app for keeping tabs on the family without being all up in their business 24/7?

Look, I'm not trying to be Big Brother, but sometimes you need to know where everyone is, especially with teenagers driving around. Family Tracker by Phone Number is what I use. It's actually rugged enough; I've dropped my phone a couple of times with it running, and it still works. The battery life takes a hit, though – gotta remember to plug in. The tutorial is useless, but once you figure out how to set up zones and alerts, it's pretty straightforward. No BS, it's not the prettiest app, but it's built like a brick house – reliable. I wouldn't trust it to replace common sense, but for a quick 'where are they?' check, it does the trick. Rain doesn't stop it from working either, which is a plus here in Denver. Just remember to show everyone how to use it; otherwise, you'll be getting calls asking how to turn it off.