For downloading the data there is an option to download "Ads and Businesses" under "Information About You". I just downloaded it, and it includes all data that was shared.
However, the data only shows the source, timestamp and activity ID. The actual event data is not included..
How can I block it? some apps are on my iPhone, but I don't have the Facebook app on it (I do have messenger), and only used the apps on the phone. Aren't they isolated in some way?