Facebook's shares have fallen sharply, after the company posted a $157 million loss for the first quarter after its flotation.
Revenues were $1.81 billion for the three months ending 30 June, a little ahead of analysts' expectations. But shares had already fallen to just $26.84 as the stock market closed. They continued to fall after, reaching an all-time low of just $23.75 - way below the $38 valuation when the company went public in May.
More importantly for the company, the number of mobile users has risen 67 percent to 543 million.
"Our goal is to help every person stay connected and every product they use be a great social experience," said founder and CEO Mark Zuckerberg, announcing the results.
"That's why we're so focused on investing in our priorities of mobile, platform and social ads to help people have these experiences with their friends."
Advertising revenues were up 28 percent compared to the same qharter last year, at $992 million, with around half of this coming from mobile.
Not everybody is convinced, though, that the company's advertising strategy is the right one.
"Marketers don’t care about Facebook’s paid ads nearly as much as they care about the site’s branded pages. But Facebook doesn’t make any money from branded pages; it only makes money from paid ads. The result? A fundamental disconnect. Facebook simply doesn’t care much what happens after an ad is shown or clicked upon," says Forrester analyst Nate Elliott.
"So when Sheryl [Sandberg] talks about ‘improving value for advertisers’ and ‘proving ROI,’ she’s trying to improve the value of, and prove the ROI of, the thing that matters least to most Facebook marketers."