The London-based company did not disclose the value of the acquisition, but reports have place the amount at between $60 and 70m (£36m and £43m).
Earlier this year Snaptu launched a Facebook mobile application, which it says works on 2,500 devices.
"We soon decided that working as part of the Facebook team offered the best opportunity to keep accelerating the pace of our product development. And joining Facebook means we can make an even bigger impact on the world," said the company in a blog post.
Last month Facebook announced its intention to enable users more users to access the site via mobile phones. "Hundreds of millions of people access Facebook from their mobile devices to share and connect with the people they care about, whenever and wherever they want. As this number continues to grow, we want to make sure that everyone has a great experience regardless of the mobile device they choose to use," it said in a blog.
This is the latest acquisition for Facebook this year. According to the Financial Times, the company has also bought messaging service company Beluga, mobile advertising group Rel8tion; and recruiting network Pursuit. The Snaptu deal is expected to close within a few weeks, says Snaptu.