SAN FRANCISCO » Trying to become even bigger — and make more money — Facebook will allow users to reveal a little less.
The social network announced Wednesday that when its 1.3 billion users log in to other websites or mobile apps through their Facebook identities, they will be able to limit what they reveal to the site or app to just their email addresses and public profile information like name and gender. Before, depending on the app or site, the simple act of using the Facebook login exposed much of their Facebook information to that app or site.
The social network also announced that it was testing a feature to allow people to use their Facebook identity to log in to other sites or apps through a button marked "Log in anonymously."
Users who chose that button would not be anonymous to Facebook, which will continue to collect the information about what apps its users are active on — data that is useful for targeting ads. But no personal information would be revealed to the outside service.
Both these moves respond to longtime complaints raised by many users who object to requests for personal data, and who object to being asked to log in through Facebook. Even Mark Zuckerberg, Facebook’s co-founder and chief executive, seems to share these concerns.
"I install a lot of apps," Zuckerberg said in an interview at the company’s conference for application developers on Wednesday in San Francisco. "If it looks like it’s kind of sketchy, no, I don’t want to give it access to my messages and every part of Facebook. I think that’s something a lot of people can empathize with."
While the changed rules involving Facebook logins are likely to be popular with Facebook users, app developers will lose access to valuable information about their customers.
But Facebook is offering them other inducements to work with the social network. The company formally announced a new mobile ad network that can tap Facebook’s knowledge of its users to place targeted ads inside other companies’ apps, with Facebook and the app maker sharing the revenue.
Zuckerberg’s long-term goal is to make Facebook a platform on which many other apps run, with Facebook accounts used as a universal identity card to log in everywhere. Widespread use of Facebook identities would give the social network valuable data to help sell more ads, keep users attached to the service and increase the company’s influence in the tech world.