Social media posts land people in trouble, so it only makes sense that a slew of  mobile apps have cropped up to allow for anonymous social media. Secret, Whisper and Yik Yak liberate users to ask questions and post musings that they would otherwise not post.

While the apps are growing quickly and attracting venture capital funding, their downside has been exposed as well. Concerns have been raised that anonymous “users can too easily spread false rumors, malign people by name and bully their peers,” The Los Angeles Times reported.

Yik Yak, which launched in December, was taken down in Chicago in March when middle and high school students went on it to cyber-bully classmates. Another high school was shut down when an anonymous bomb threat was posted. Yik Yak is now keeping closer watch on posts and has blocked usage of the app at middle and high schools.

Websites such as Ask.fm and 4chan already allow users to post anonymously. The mobile apps are an evolution seen seen as an alternative to Facebook, Twitter and other social media networks becoming “a forum for feel-good comments and self-promotion,” said USC’s Annenberg School of Communication and Journalism social media expert Karen North.

“People are not hard-wired to keep secrets or even to want to keep secrets,” said North.

San Francisco-based start-up Secret launched in late January and has raised more than $10 million, including $8.6 million from Google Ventures. Chrys Bader-Wechseler, one of Secret’s founders, said “Facebook has ‘become saturated and everybody you know is on it … it’s very hard to share something that’s really personal because it goes out to this mixed audience and it stays permanent on your profile.”