"People are posting stuff and they think it's a closed network. They think you're just sharing things between friends," said Mike Metzler, who's a Snapchat strategist. He creates social media campaigns for major organizations.
What Metzler knows, and those who post questionable videos, is that Snapchat has a feature called Snapmap.
"It geotags that specific video and puts it on a global map and it goes everywhere. It also tells people where you are. A lot of users don't realize that the feature can be disabled," Metzler said.
The video that most people think disappears within 24 hours can also be saved by those who view it.
That's what led to Tuesday's arrest of 20-year-old Mason Kirby Gray. He was charged with two armed robberies at a pair of gas stations in west Harris County last year.
Alleged Snapchat shooter wanted in 2 armed robberies arrested by deputies
Alleged Snapchat shooter wanted in 2 armed robberies arrested
He couldn't be found until he posted the Snapchat video, which showed him firing off shots while he drove. That video was found by robbery detectives, and Gray was arrested at a friend's house Tuesday.
"He had already imprisoned himself," said Lt Jeff Steuber. "He just played video games all day because he couldn't go outside. He knew people were looking for him."
"It's the same payoff for anyone who does something stupid," said Metzler of the questionable videos. "They do it to impress their friends."
It also helps law enforcement. Of Gray, Steubner said, "he put himself out there with what he's doing, and in the end that's what helped us get him."
Man seen shooting out car window on Snapchat now wanted for aggravated robberies
Alleged Snapchat shooter now wanted for aggravated robberies
RAW VIDEO: Reporter Chauncy Glover questions alleged Shapchat shooter
Alleged Snapchat shooter booked into Harris County Jail
WATCH: Alleged Snapchat shooter in custody
Alleged Snapchat shooter wanted in 2 armed robberies arrested
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