Facebook chief Mark Zuckerberg announced Tuesday the world's largest social network will soon include a new dating feature -- while vowing to make privacy protection its top priority in the wake of the Cambridge Analytica scandal.

Zuckerberg unveiled the plans as he addressed Facebook's annual F8 developers conference in San Jose, California -- emphasizing that the focus would be on helping people find long-term partners.

"This is going to be for building real, long-term relationships, not just hookups," Zuckerberg said in presenting the new feature, noting that one in three marriages in the United States start online -- and that some 200 million Facebook users identify as being single.

Under the new feature, users will be able to create a separate "dating" profile not visible to their network of friends, with potential matches recommended based on dating preferences, points in common and mutual acquaintances.

It will be free of charge, in line with Facebook's core offering. The announcement sent shares in the online dating giant Match.com tumbling, finishing the formal trading day down 22 percent.

The 33-year-old CEO also said the dating offer was built from the ground up with privacy and safety in mind, as he underscored the firm's commitment to boosting privacy protections.

In a related move, Facebook announced an upcoming feature called "Clear History" that will allow users to see which apps and websites send the network information, delete the data from their account, and prevent Facebook from storing it.