It's the younger generation's way of passing notes.
"A lot of kids at school use it just like during class when they're bored or something like that," says Dylan Weber, a junior at DeWitt High School.
He's talking about Snapchat, the free app available on iPhone and Android. It's so popular, it's in the top 10 free apps on iTunes.
"Everyone always talks about, 'Oh! I got a Snapchat!" says Audrey Kahler, a senior at DeWitt High School.
The company says users send 60 million snaps a day.
"It's just something fun to do," Kahler explains. "You can do silly faces or things without your friends having evidence."
"You can actually see the person's face," echoes Weber. "It's a good way to connect with friends."
Users take a picture or video and send it to friends. They choose how long that person or group can see it, 10 seconds or less, before it self destructs.
"My concern as a parent with that is, you always hear that once it's on the Internet, it never really goes away," says Linda Kahler, Audrey's mother. "So where does it go after 10 seconds or three seconds?"
Depending on who's receiving it, it's probably deleted through the app. It may, however, be screen grabbed, which the app should tell you. But once someone takes a screen shot, or takes a picture of the photo with another phone or camera, that person has a copy of whatever was snapped and can post it somewhere else.
"Regardless of your age, you need to understand the consequences of every photograph that you take," says Det. Sgt. Jay Poupard of Michigan State Police. Poupard is in MSP's Computer Crimes Unit.
He knows all too well what can happen on the receiving end of that snap.
"I've seen those images that a child thought was going to be given to a trusted friend or somebody that they thought was a trusted friend that they didn't really know in real life, and they shared that picture and then that person, that predator, would choose to use that picture to extort that child to take more pictures, more inappropriate pictures of themselves," Poupard says. "Just by installing the application, you have access to probably hundreds of thousands of images."
Regardless of whether teens are Snapchatting their friends or strangers, the app is rated 12 and up for infrequent or mild:
--Sexual content or nudity
--Alcohol, tobacco or drug use or references
--Profanity or crude humor
--Mature or suggestive themes
"I think most parents would probably choose absolutely not to allow their child to use an application like that," says Poupard.
There is a security setting that lets users choose whether to allow "everyone" to Snapchat you, or just "friends."
There is also a way to screen grab an image via Snapchat without the sender ever being alerted that the recipient saved a copy of the image. You can watch the video above to see how it works.