Google builds the browser, so I follow that, but how so with Facebook?
If you are talking about the in-app browser, this is an interesting grey area that we should be able to define generically.
If you are talking about the in-app browser, this is an interesting grey area that we should be able to define generically.
The FB app ID is also one of the most common meta tags behind Open Graph.
A nice small example of what this can do can be seen with Clearbit [0] which does a good job of telling you where someone works based off of nothing but their IP address. Imagine that but with the exponentially larger data warehouses of Facebook or Google, paired with referrer tags (FB has CLIDs that allow them but not you to match clicks to actual users) and meta tags (FB can tell exactly what app, page etc a website is associated with and use that data to advertise to users).