Most people forget that when they download an app or sign into a website with Facebook, they are giving those companies a look into their Facebook profile. Your profile can often include your email address and phone number as well as your work history and current location. And most people don’t realise that if you’re sharing that data with friends, then apps used by those friends can see that data as well!
For the sake of convenience, ease and connectivity, many people use their Facebook profile to sign into many different websites, or access many different apps. What they forget, or don't realize in many cases, is that this gives those website access to their information as well as that of their friends. It allows companies to track and potentially influence behavior, both on and offline. Advanced Facebook Retargeting Audiences: Up Your Facebook Ads Game With Custom Retargeting Audiences
I often hear people say they are free from Facebook tracking because they do not have an account. Well, the joke is on them (or us? All of us?!). One of the reasons Facebook’s advertising works so well is the immense amount of websites and services feeding data back to Facebook’s advertising arm. That includes data gathered using the methods laid out above.
There used to be a couple of different kinds of pixels: The Facebook conversion pixel and the Facebook custom audience pixel. Facebook discontinued the conversion tracking pixel back in 2017. If you were using the Facebook conversion pixel, you’ll need to switch over. You can learn how to do so in this Facebook business help article. If you were using the old custom audience pixel, these instructions explain how to upgrade to the current pixel.
When people sign up for Facebook, they’re encouraged to upload their contacts to make it easier for Facebook to connect them with their friends. That allows Facebook to access personal contact information for people who never signed up for the platform or gave their permission to share their information. Facebook knows that these contacts are friends of the new Facebook user, and can start compiling additional details on these non-members. Facebook Ads Retargeting Tutorial 2019 (Easy 10X ROAS) - Shopify Dropshipping
Whether or not Facebook is tracking your browsing even when you're logged out, if you don't want third-party sites to send data to Facebook, you have some options. You could scrub your system clean of all Facebook.com cookies every time you use Facebook, but a number of developers have already stepped up with browser extensions to block Facebook services on third-party sites. Here are a few: Setup Retargeting Ads on Facebook in 4 Minutes