Facebook snapped up the hugely popular photo-sharing app Instagram Monday, for roughly $1 billion in a combination of cash and stock.

Facebook CEO Mark Zuckerberg announced the acquisition in a post on his Facebook Timeline Monday.

The sale is expected to close later this quarter, and will bring the nine-person staff of Instagram to the social network.

“For years, we've focused on building the best experience for sharing photos with your friends and family," Zuckerberg said in the post. "Now, we'll be able to work even more closely with the Instagram team to also offer the best experiences for sharing beautiful mobile photos with people based on your interests.”

Zuckerberg went on to say that the company will be building on Instagram's strengths and features and growing the app independently rather than “just trying to integrate everything into Facebook.” Facebook plans on keeping features within the app that allow photos to be published on other social networks, and the ability to have followers and follow people who are not necessarily your Facebook friends.

"We will try to learn from Instagram's experience to build similar features into our other products," Zuckerberg said. "At the same time, we will try to help Instagram continue to grow by using Facebook's strong engineering team and infrastructure."

Instagram CEO Kevin Systrom echoed Zuckerberg's statements on the Instagram company blog adding "We’re psyched to be joining Facebook and are excited to build a better Instagram for everyone."

Instagram launched its iOS app in October 2010, and came to Android for the first time last week. This is the first time Facebook has acquired a company or product with so many users. “We don't plan on doing many more of these, if any at all." Zuckerberg said. “But providing the best photo sharing experience is one reason why so many people love Facebook and we knew it would be worth bringing these two companies together.”

What do you think this means for the photo-sharing app — and how will it boost the social network? Let us know your thoughts in the comments.

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