Facebook to revamp privacy controls

* Users can customize privacy settings with every post

* Facebook will let users share more location data

* Changes to become available on Thursday

SAN FRANCISCO, Aug 23 (Reuters) - Facebook is making it easier for users to control who sees their information, and to have more say over the photographs they appear in, as the world's No. 1 social networking service seeks to assuage privacy concerns.

The changes will enable Facebook's 750 million users to quickly access and modify their privacy settings each time they share information on the online network, rather than forcing them to click through various specialized sections of the website.

When a person uploads a photograph to Facebook and "tags," or labels, their friends in the picture, the friends will now have the power to approve the tag before the picture is linked to their personal profiles. Previously, users could only un-tag themselves from undesirable photos after the fact.

Privacy has been an ongoing challenge for advertising-supported Facebook, which must balance its commercial interests in having people share more of their lives on the service with users' sensitivities about having sufficient control over their personal information.

Last year, Facebook Chief Executive Mark Zuckerberg rolled out simplified privacy settings -- which at one time required users to tinker with more than 150 different options -- amid complaints by some users and privacy advocates.

Facebook also recently raised privacy hackles when it expanded the use of a facial recognition technology that automatically identifies people in photographs.

The latest changes come as Facebook is facing its most significant competition in the social networking market in years, following the recent launch of Google Inc's rival service, Google+.

The new service, which enrolled 10 million users in its first two weeks, has touted its ability to let people organize their friends and contacts into different groups, thus offering fine-tuned privacy controls as a key advantage over Facebook.

Facebook Vice President of Product Chris Cox said the changes had been in the works for months and are intended to address several long-standing requests from users, rather than matching the competition.

"As long as people don't feel like that part of the tool is awesome, [then] we have work to do independent of Google or anyone," said Cox.

Among the new features, which Facebook will introduce on Thursday, will be a drop-down menu that allows Facebook users to specify the intended audience for each message or photograph they share on the network, as well as the ability to alter who can see a message after it has already been posted online.

Facebook also added a special button to make it easier for people to check how their online profile and activity appears from the perspective of another individual, such as a boss or an ex-girlfriend.

Even as Facebook offers new privacy controls, the company is introducing new features that could cause some privacy concerns.

Facebook users will now be able to tag anyone in a photograph, loosening the previous policy in which users could only tag people with whom they were friends. The change will be paired with new safeguards, including the ability for users to approve any tags that link to their profile and the ability to block a specific person from tagging them in photos.

Facebook is also seeking to incorporate more data about its users' various locations into the service. New features will allow users to specify the physical whereabouts of items they share on the service, such as a restaurant mentioned or the setting of a photo, as well as the location from which they are posting information to Facebook.

While Facebook users will need to consent to share their location when they post messages on the social network, some users may not understand that this is in fact occurring based on the description that Facebook provides, said Justin Brookman, the director of the Consumer Privacy Project at the nonprofit Center for Democracy and Technology.

"There may be some bumps in the road as people get used to that feature," he said.