Facebook to let users limit data revealed by log-ins

Trying to become even bigger - and make more money - Facebook will allow users to reveal a little less.

The social network announced on 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 log-in exposed much of their Facebook information to that app or site.

The social network also announced 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 choose 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 empathise with, and we just want to give them the tools to help mediate that."

While the changed rules involving Facebook log-ins 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. Facebook had already been testing this network on a smaller scale for several months.

Google and Twitter offer app developers access to similar ad networks.

Zuckerberg said Facebook's "Log in anonymously" button would also persuade more people to try new apps.

©2014 The New York Times News Service