Stealthgenie has this feature. Though most kids rarely talk anymore. Just check your usage from your carrier and you will probably find that very few calls are actually made. As far as the third party laws go, as a parent letting your kids know that at any time you can monitor, read, view, the phone they are using is a disclaimer. Just like the " All calls can be monitorred for quality assurance" message. If your kids are over 18, 17 in some states, you may have an issue. However, once you look at what the usage of calls compared to imessage, facebook, pintrest, istagram, etc is, the call issue will be the least of your concerns. I know not everyone agrees with taking the stance that you are, but I'm sure you have your reasons. If being paranoid, or untrustworthy by other people's standards, saves your kids pain or from making a really stupid decision then so be it. Kids can have privacy when they turn 18 and move out. The web site for stealthgenie also offers live chat, so you can confirm the legality of your particular circumstance prior to purchase. Also know that no software like this currently works with IOS7 and the device will have to be jailbroke. Good luck to you.