I have a bone to pick about iMessage, a new feature for Apple's iPhone, iPod touch and iPad that users — especially families — need to know about. And boy did I ever learn the hard way.

iMessage allows iOS device users to send free text messages, even pictures and video, to other iPhone/iPod touch/iPad users.

That's a great feature, especially for someone like me who doesn't want to pay for text messaging (that's $15 a month extra or $180 per year for each person). Now I can text with my daughter and wife and not pay extra. But there's an unfortunate problem with how iMessage initially is set up.

My wife and I were lying in bed, and I wanted to show her how iMessage works. I picked up my iPad and sent her a pithy, but horribly vulgar little message just to be a smart aleck and get a rise out of her. It was a rather obscene (nay, VERY obscene) quote from the movie "This is Spinal Tap" that is too gross to repeat here. She saw the message and screamed in shock. I laughed. Mission accomplished.

Unbeknownst to me, my salty message also was sent to my 14-year-old daughter's iPhone. We got a text back from her asking what in the heck my message was about.

All my efforts to keep her from seeing R-rated movies just went down the toilet. I'm now in the doghouse with my wife for six or seven years — five if I'm lucky.

While regular SMS texting works with your cell phone number, iMessage works with a user's Apple ID, the personal login for iTunes and your iPhone (which is usually your email address). So when you send a text through iMessage, it isn't sent via a number, but rather through the Apple ID.

So a message sent to one Apple ID appears on every iDevice logged in to that ID.

My daughter's iPhone uses my Apple ID, and I had just set up my wife's new iPhone 4S with my Apple ID. We link them all to just my Apple ID, as many families do, so we only have to buy one copy of apps and songs from iTunes and then share them.

So if you have multiple iPhones and iPads in the house, heed my lesson here.

What I didn't know is you can change iMessage's settings so it can be tied to a different Apple ID than the one you use for iTunes Store purchases. In the set up, it never asks you if you want to use a different ID, and there is no documentation, even on Apple's site, that says you can change it. Even the Apple tech support people I called and the Apple Genius Bar person I talked to at one of the stores didn't know about this. I had to find out for myself with a lot of research.

Apple needs to make iMessage a more workable and simpler feature, and maybe other idiot husbands and fathers like myself — my horrible sense of humor notwithstanding — won't make the same mistake I did.

If you have a tech question for Vince, email him at ohmytech@sltrib.com and he'll try to answer it for his column in The Salt Lake Tribune or its website. For an archive, go to www.sltrib.com/topics/ohmytech.