Smartphone screen with Facebook and Phone app icons in detailVARIOUS

On the eve of launching a customer feedback tool to monitor bad behavior from Facebook advertisers, the social giant has revealed more about how it keeps tabs on everyone else.

During marathon testimony on Capitol Hill in April, chief executive officer Mark Zuckerberg punted on some questions from lawmakers regarding his company’s handling of data and its approach to user privacy. Now Facebook has submitted those answers in a 200-plus page document that follows up on Zuckerberg’s testimony and was recently released by the Senate.

Naturally, the network gathers information on what happens on its platform, such as time spent and the sales it helps transact. But it can also go beyond its own borders to track user behavior on other apps and sites. A bit of code called a “pixel” allows the tech company to monitor actions after a person clicks on a Facebook ad, so it can supply insights to advertisers.

The data includes shopping and other activities and is collected regardless of whether the user is logged into Facebook at the time. The tracking extends to local interactions on the device itself, including mouse gestures, which can be used to distinguish between humans and bots. And if users sync contacts to find friends they know, they may have also given the company access to their call logs and text history.

Other data up for grabs: The type of device used to log in to Facebook, the Internet service provider or cellular carrier that provides the connection, which browser plug-ins or extensions have been installed, the gadget’s battery level and remaining storage.

Facebook is not the only tech company to track users and share information with partners, and in fact, it pointed this out in the report by citing Google. There are also limits to what it will monitor, the company said. It won’t hijack device cameras or use microphones to surveil conversations. This promise matters even more, in light of Facebook’s ownership of virtual reality company Oculus, which is responsible for some of the key software and hardware in one of the buzziest areas of tech today.

The renewed scrutiny over Facebook’s handling of user data may overshadow its steps to keep better tabs on advertisers, although those actions might ultimately mean more to brands and retailers in the short term.

Facebook offers a new shopper feedback tool and satisfaction scores.  Courtesy photo

On Tuesday, the company introduced a feedback tool that lets customers review businesses after a purchase. “People tell us they don’t like feeling disappointed by businesses who don’t meet their expectations of product quality and shipping times,” said Sarah Epps, product marketing director of ads at Facebook.

The tool feeds an overall satisfaction score that’s visible to the business, but not users. So users won’t be able to peruse them like Yelp reviews, at least not anytime soon. But Facebook certainly can and plans to work with businesses to improve their score. If that doesn’t work, the social network will ultimately limit their ad-buying powers.

In other words, advertising partners beware: Keep disappointing customers and Facebook will swoop in to undercut your social reach.

As for how Facebook itself uses people’s data, all eyes are on Congress to see what it will do next.