Shares of Facebook drop on guidance, increased costs

Facebook reported third-earnings of 43 cents per share, versus expectations of 40 cents per share.

The stock fell in after-hours trading.

Analysts had expected Facebook to report earnings of about 40 cents per share on $3.12 billion in revenue, according to a consensus estimate from Thomson Reuters.

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In addition to Facebook's revenue and user growth in the third quarter, investors will be looking ahead to important new initiatives set to be released in the coming months.

Facebook has 'upcoming catalysts, new revenue streams like autoplay video ads, Instagram monetization and people are going to want to buy the stock before that starts rolling out, and it's rolling out in the next three to six months,' said Mark Mahaney, an analyst at RBC Capital Markets, on CNBC's 'Squawk on the Street' on Monday.

Social media rival Twitter suffered a wave of downgrades and a plummeting stock price after it announced its earnings on Monday. In addition to light guidance, some investors were spooked by slowing user growth.

As with Twitter, Wall Street will be looking to Facebook's mobile advertising figures-widely considered to be the headline for monetizing the future of social media.

Read More Here's what Wall Street was expecting from Facebook earnings

-CNBC's Everett Rosenfeld contributed to this report.