BY ALEXEI ORESKOVIC SAN FRANCISCO Wed Apr 30, 2014 7:02pm EDT 

(Reuters) - Facebook introduced new features on Wednesday that let users limit how much personal information they share with third-party mobile apps, a move meant to quell privacy concerns as the social network seeks to become a top entry port to the Internet.

In recent years, Facebook Inc has successfully encouraged a growing number of third-party app makers to allow users to log in with their Facebook identity rather than, say, by entering an email address or creating a dedicated account.

The result has been an influx of valuable data for the world's No. 1 social network, but concerns have also mounted about third-party developers gaining access to private information.

Chief Executive Mark Zuckerberg said at Facebook's developer conference in San Francisco on Wednesday that a new version of Facebook's log-in tool, called "log in anonymously," would let users control what information they allow third-party apps to see. He told developers the tool would let users feel more comfortable about logging into apps using Facebook.

"By giving people more power and control, they're going to trust all the apps that we build more, and over time use them more. And that's positive for everyone," said Zuckerberg.

The revamped log-in screen will let users select which personal information stored on the social network, such as an email address, birthday or items that they have "liked" on Facebook, can be accessed by any particular app.

The user's names and gender will remain visible to the app.

On Wednesday, the social network also rolled out a new service to distribute ads across a network of mobile applications, opening the door to a new source of revenue.

The service, which has been in the works on for some time, allows mobile-app makers to insert various ads within their software, with Facebook sharing advertising dollars with the developers.

"This is really the first time that we're going to help you monetize in a serious way on mobile," Zuckerberg said.

Facebook faces tough competition in the active mobile ad network market. Google Inc's AdMob service already allows advertisers to distribute ads to mobile apps, while Twitter Inc said on Tuesday that its MoPub ad network can reach 1 billion mobile users.

Twitter's MoPub, which serves as an advertising management tool for app publishers, will allow mobile apps to feature ads for the Facebook audience as well as other networks, the two companies said.

Facebook began testing a mobile ad network with a limited number of advertisers and mobile app publishers in January. It plans to expand the number of app makers that can use the service, although it did not provide a time frame for when the system will become broadly available.

The new mobile ad system, dubbed the Facebook Audience Network, will leverage Facebook's more than 1 million advertisers and its own ability to target users based on their traits.

Facebook generates the bulk of its revenue from ads that appear on its own Web pages and within its own mobile app. By distributing ads across a constellation of independent mobile apps, Facebook effectively expands its advertising space, opening the door to more revenue.

To get access to the extra ad space, ad networks typically share the revenue with their partners. Facebook will share most of the ad revenue with apps makers, as is standard in the industry, a source familiar with the matter told Reuters.

(Reporting by Alexei Oreskovic; Editing by Phil Berlowitz and Andre Grenon)