UCLA students explain Snapchat and sexting

"Facebook is ancient, Snapchat's just old."

Wise words from Khalid McCaskill, a student at UCLA. McCaskill typifies today's social media user: young, engaged and showing about as much loyalty to one platform as Zsa Zsa Gabor did to marriage. (Google that one, kids.)

Keeping young people like McCaskill interested is job #1 for the social media industry. Mark Zuckerberg just turned 30. That's 80 in mobile-messaging years.

Last week on the UCLA campus in Westwood, California, I spoke with several students about their preferred methods of communication. I struck gold, coming back with some of the most insightful and hilarious man-on-the-street interviews in a long time.

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Bottom line: Snapchat may be "old," but it remains very popular because it's quick, easy, and users like the fact that whatever you post disappears after a few seconds. Perhaps that's why Facebook is now reportedly working on a competitor called Slingshot.

Here's a quick snapshot of Snapchat's pros and cons.

"Snapchat's fun," said 19-year-old Casey Leonard. "It's a lot less formal than texting. It's odd to think of texting as formal, but it kind of is."

"I use it more than I talk to people on the phone because it's so convenient," said Muhib Yusufi. "With the new update, you can literally slide to the right and you can start chatting, face-timing, everything."

"I don't like Instagram anymore, because of too many fake artists or wannabe models," said Ahmad Azzawi, talking to me in between shouting to friends walking by on campus ("I Snapchat him.") Azzawi likes the fact that if someone posts something lame on Snapchat, at least it quickly disappears. But what if they post something really good? "Honestly," Azzawi said, "you've got to live in the moment sometimes."

Celine Linarte prefers Facebook for social interaction, "as opposed to Snapchat, which is only pictures of random things that you see throughout the day." While she likes the way Snapchat lets her share photos instantly with several people at once, "What I do not like about it is you cannot save photos or videos."

Casey Leonard said Snapchat creates its own sense of peer pressure. "Sometimes if you're not feeling photogenic and somebody sends you a picture, there's, like, pressure to respond."

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Then there's Snapchat's anonymity. "Sometimes I get random people adding me, and I don't know who they are," said Yusufi, "but with Facebook and Instagram, you have their whole, like, entire background, and you see how the person is, based on what they post."

Any stories of Snapchats gone bad? Azzawi has a few, mostly involving friends who are sleeping: "Someone will take a Snapchat of them and draw, you know, very nasty things."

Most news reports about Snapchat describe it as the perfect tool for "sexting," as any inappropriate content quickly disappears. Is that really what it's mostly used for? "I don't really think so at all," said Linarte. "That's not so much a thing," agreed Leonard.

Really?

"No, no," said McCaskill, before pausing and changing his mind with a smile. "Yeah, yeah it is."

As for Azzawi and Yusufi, when asked if Snapchat is all about sexting, their faces go blank. "What's that? I don't do that," said one with a deadpan look. "I don't even know what that is," said the other.

What could replace Snapchat was a question no millennial I spoke to seemed able to answer. "I couldn't tell you, you're asking the wrong person," said Leonard. "I'm behind the curve so to speak."

Behind the curve at 19 years old. That's, like, 40 in Snapchat years.

—By CNBC's Jane Wells.