Bieber-backed selfie app holds promise: CEO

As Facebook battles a teen exodus, an app backed by pop star Justin Bieber is drawing them in.

Shots, a selfie-only app, which launched in November, hit 2 million users this week, with 75 percent of them women between the ages of 18 to 24, a key demographic for Facebook and Twitter.

Shots boasts that it is the safe social network. With no comments or public messages, it's looking to push out negative attacks on individuals. The selfie app doesn't allow you to post regular photos from your phone and only allows you to post from the front-facing camera lens.

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"Part of message also is to reduce the amount of bullying and most of the bullying is happening inside comments. And since it's your face that's out there, which is something we never want to have criticized, we eliminated comments," Shots CEO and co-founder John Shahidi said Monday on CNBC's "Fast Money."

The app has grown in part due to of social media sharing. Shots has 535,000 followers on Twitter, and each tweet gets about 1,000 retweets.

Pop star Bieber, an investor in the company, frequently tweets out photos from the app and has 53 million followers.

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In total, Shots has brought in $2.7 million in funding and just launched the Android version of its app earlier this month.

By CNBC's Kristin Cwalinski