Dr. Wes: The Ugly Meter. Sounds like something from a young adult novel, but it’s actually an app a lot of teens and tweens have downloaded to their phones.

It helps them determine with great accuracy just how unattractive they and their friends really are.

Seriously? Nope. It’s just a random number generator. A prank. Something to astound your friends at a bar on a Saturday night when you’ve had a couple of beers and are feeling a little pesky. “Hey look dude. I just pulled down this gnarly app that’ll prove you’ve got the nastiest mug in the place. Heh heh. Look here. It gave you a nine, man!”

Wait. Something’s wrong with my little scenario. What’s your 14-year-old kid doing at a bar? Exactly my point. The Ugly Meter really got its big break on Howard Stern’s XM radio show, the kind of entertainment we want our teens digging into on a school morning.

I recently did a segment on St. Louis Channel 5 (find it at dr-wes.com) that was tackling this problem as another kind of bullying, that kids were apparently using this silly app to make fun of each other.

And therein lies the rub. What’s funny (apparently) for adults is mean when used by kids.

Even dumb humor takes a certain level of abstract reasoning, and that only comes at the end of adolescence. Tweens and early teens find fun in something like the Ugly Meter not because it’s self-deprecating or a good-natured joke between buddies, but because it insults and hurts other’s feelings. For kids, that’s what’s funny about it. Like giving someone a wedgie in front of the whole class or posting a YouTube of their most embarrassing moment.

I’m pretty sure “The Dapper Gentlemen” didn’t have that in mind when they thought this app up. I suspect they thought, “Toss me another beer, dude, and lets code out something really dumb.”

For teens, the best thing about The Ugly Meter and similar humor is that it can start a dialog between parents and kids about what’s funny versus what’s hurtful and why.

While I wouldn’t make a big deal out of your kid having The Ugly Meter on his phone, I’d treat it like every other app and have a serious discussion of its real purpose and ethical use — which isn’t much, actually. In fact, I recommend Angry Birds over this thing any day.

Miranda: While I won’t be downloading The Ugly Meter anytime soon, I can see the scenario in my head just as Wes describes: A group of middle school kids passing an iPhone around and mocking each other, or bullying someone who’s number jumps off the screen.

This technology, which can be downloaded straight to the phone without parental consent, is why parents need to keep a good eye on what their preteens are doing on their smart phones.

Movie ratings were invented so parents knew what to expect when they showed up at the theater. Video game ratings worked the same way. Their sole purpose is to avoid exposing young teens to content that is too mature for them.

But iPhone apps don’t have these ratings (however good an idea that might be), so it is up to parents to decide what content their child is and is not allowed to download.

Though many adults will not understand the harm of this prank app, parents also have to remember that along with R-rated movies and excessively violent video games, the type of humor their kids are exposed to needs to be monitored as well.

Ask yourself how you would feel as a 14-year-old, already uncomfortable in your own skin, if somebody’s phone said you weren’t terribly unattractive. Not too great, I would imagine.

There is no stopping your kid from coming in contact with nonsense like this, even if you don’t allow the app to stay on their phone.

But this is again another opportunity to review your family’s guidelines on technology. It is essential to measure your own child’s maturity and know what they are capable of handling, then making a plan for their use of technology.