Introduced at Demo, Ambit Control is parental spyware for kids' smartphones. In addition to telling you where a kid's phone is, via the phone's GPS radio, a phone with Ambit on it will tattle when a kid installs an app. You can also configure an Ambit phone to allow calls or texts to only specific numbers. Children can be told that their phone is tapped, or, as the company CEO said from stage, you can just give your kid a phone with Ambit without telling them that they're being watched.
Since the app needs to run and hide in the background processes of the phone it's installed on, it works fine on Android phones but not so much on iPhones, which don't support multitasking of consumer apps. That might be a problem considering the effectiveness of Apple's advertising to younger users.
As a parent, I find this concept attractive, but I caution parents that spying on your kids without telling them you're doing so is bound to have repercussions as they get older.
I expect this service to become available eventually from mobile carriers, probably at an inflated monthly subscription price.