Toys R Us just released a new 7-inch tablet aimed at the growing demand for kid-friendly mobile devices. But it’s not just tablets. It’s smartphones, too.

The Tabeo from Toys R Us highlights the emerging niche of teens and children within the mobile marketplace, despite doubts regarding the compatibility of kids and high-priced electronics.

So, I had to get a new phone a couple months back, right before a trip to visit my family. I showed up with a brand new iPhone 4S (white, no less), which my nephew and nieces immediately clamored to get a hold of.

“What games do you have on it?” (Because that’s what smartphones mean to kids: games.)

You know what I told them? “No games, sorry.” And I kept the phone in my pocket, despite the whining.

Here’s why… Not even two weeks before I visited, my sister’s smartphone was drowned in the toilet at the hands of an adorable 3-year-old girl.

Before that, the phone went through a series of “glitches,” including deleted contacts, reprogrammed settings, unauthorized game purchases, a cracked screen…and, of course, long-distance phone calls to Asia (we’re still not sure how a 6-year-old accomplished that, repeatedly).

Kids break stuff. They don’t always listen to or pay attention to rules. They’re rough on things just for the fun of it. I don’t think anyone will argue that kids are a safe bet for electronics.

Yet there’s no doubt that they want them. Of course they do. Kids want to play with the same gadgets their parents are playing with (oh, we’re playing).

In fact, it appears kids want the stuff more than we do. According to a new Nielsen survey, teens are the fastest-growing segment of smartphone owners.

Read about it in Mobile Market: Teen Buying Power…