Airbnb, Tinder, British Airways, Duolingo, Spotify and even Marketplace are just some of the hundreds of websites that Facebook says have shared my data with the social network. Just from those you can probably work out more about me than I might want to share. This is all part of Facebook’s Off-Facebook Activity, its new tracking tool that went into wide release yesterday. It lists all of the companies and websites that share activity, like views, purchases or even just when you open an app. Facebook uses all that data to allow advertisers to create messages that are tightly targeted to you and your interests.