The best way to know where your teenagers are is to have the kind of relationship with them in which they tell you -- truthfully. But for those whose relationships are a bit strained, well, there's an app for that. Here is a list of some apps that will help protect your cover as you track your teens' online comings and goings:

1. mSpy﻿

2. The Spy Bubble

The Spy Bubble is another jack-of-all-spying-trades, also suitable for monitoring the phone of your suspected cheating spouse. Its site does offer some cautionary, if frightening, state-of-the-world information you might find useful. We are still reeling from this one about online photos and Photoshop: "Never let your kids share their photos online on an open forum. Why? They will ask. Everyone does that. Yes, everyone does that and about eight percent of those experience harassment due to photoshop effects on their photos. The worst bullying of this sort is seen by the girls, especially because female reputation is one of the most fragile things in the world."

3. The Phone Sheriff

One nice feature of the Phone Sheriff is that it allows you to set time limits on your teen's device. Want "OK, you can play with your phone for an hour" to really mean just 60 minutes? This app will shut down and lock the phone when you tell it to.

4. Mobicip

Mobicip isn't so much a tracker app as one that restores a bit of control over your teen's online life. The middle school level blocks online shopping, gambling, dating, liquor, and chat sites. The high school level blocks content that is adult, sexual, or involves weapons and violence. Good luck with your kid not using a friend's phone.

5. MamaBear

For parents of new drivers and parents of teens with friends who have had their licenses for 20 minutes, MamaBear will let you know the speed of the vehicle your teen is traveling in. Just don't text them to slow down, OK?

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