"The Spool team has deep expertise in mobile software development and a passion for making content easy to consume," Facebook said Monday in response to an AFP inquiry.
"We're excited for the team to join and accelerate their vision at Facebook."
Financial terms of the acquisition were not disclosed.
Spool let people organize online content using bookmarks so they could access digital stories, videos or other material at their leisure or on different Internet-linked gadgets.
"We started Spool to make content easy to consume on a mobile device," the startup said in a blog post telling users the service was closed and the team joining the world's leading social network.
"We firmly believe that solving these problems will be increasingly important as the world accesses the Internet primarily through mobile devices."
Facebook, which has its headquarters in the California city of Menlo Park, has made a priority of improving its mobile offerings to keep in synch with users who are increasingly accessing the service from smartphones or tablets.
Lack of a clear strategy for making money from users who connect to the social network with mobile devices was considered to be among the reasons Facebook stock sank below its debut price of $38 per share in May of this year.
Facebook shares were trading at slightly less than $30 on the Nasdaq in New York Monday.