First, parents worried about their children being approached by predators at grocery stores and on playgrounds. Then the threat moved online via shady profiles on social media.
Now, authorities say, some phone apps have opened even more channels of communication between adult predators and minors -- including some video games like Fortnite and Minecraft.
Earlier this week, in announcing the arrests of 24 alleged predators, state Attorney General Gurbir Grewal warned the public that people looking to take advantage of young teens and children have more options to do so than ever due to the ever-developing landscape of internet communication.
"It is a frightening reality that sexual predators are lurking on social media, ready to strike if they find a child who is vulnerable," Grewal said in describing how the 24 suspects were attempting to lure and illicit sex with teenagers.
Some of them -- a police sergeant, included -- posed as teenagers, themselves.
The suspects, all men, varied in age and walks of life.
But Grewal said most were taking advantage of a multitude of apps allowing them to reach out to children, or in this case, undercover detectives.
The men thought they were chatting with 14- and 15-year-old boys and girls, but were instead talking with detectives with the New Jersey State Police's Internet Crimes Against Children Task Force.
The task force trains its detectives to maintain online profiles on apps known for hooking up like Tinder and Grindr.
But Grewal said their presence can reach far beyond that.
Arrests of alleged child predators have been made after communicating through apps like Kik, Wishbone, Tumblr and even video games like Fortnite, Minecraft and Discord.
The similarities to the more social apps are that the gaming apps have a chat area.
"These arrests serve as a sobering reminder that parents should closely monitor their child's online activity," State Police Superintendent Col. Patrick Callahan said Tuesday.
Some of the apps, like Tinder, have an 18+ age requirement, but users are able to enter a birth date that's older or younger than they actually are. A person's age listed on Facebook sets their age on Tinder, as well, if the apps are synced.
But the app wasn't always adult-only.
Up until June 2016, a user only had to be 13 to sign up. The company changed its requirement after being heavily criticized by parents, parentinfo.com reported.
Many other social mediums and apps, like Tumblr, Instagram and Snapchat also have a minimum age requirement of 13. Tumblr says it's serious about its age requirement, writing:
"You have to be the Minimum Age to use Tumblr. We're serious: it's a hard rule. "But I'm, like, almost old enough!" you plead. Nope, sorry. If you're not old enough, don't use Tumblr. Ask your parents for a PlayStation 4, or try books."
But Tumblr and other apps don't have a surefire way of keeping children off the app. If a kid can calculate a birthday that would make them older than the required age, they can access the app.
Making sure a child or teenager doesn't get wrapped up in a conversation with someone much older than they are pretending to be boils down to parents taking note of the apps their kids are using and talking through what is appropriate, authorities say.
"If children appear anxious of evasive when the topic is raised, it may be a red flag," Grewal said.
"It's critical that parents talk to their children about social media and chat apps to let them know that the people they encounter may not be who they initially seemed to be."
Paige Gross may be reached at pgross@njadvancemedia.com. Follow her on Twitter @By_paigegross
Artigo de Paige Gross para NJ.com