Last year with iOS 14.5, Apple introduced a privacy feature on iPhone allowing the user to allow, or block, app tracking.
16 billion dollars lost for social networks Facebook, YouTube, Twitter, Snapchat…?
In other words, you can prevent apps from collecting your data, which is then used to bombard you with personalized ads. A blow for the big social networks which can no longer target users with personalized advertisements. And according to a recent report by the firm Lotame, this function could cause major Tech groups to lose nearly $16 billion this year, in particular via their Snapchat, Facebook, Twitter and YouTube applications. Facebook would be the biggest loser with 12.8 billion, followed by YouTube with 2.1 billion. However, it is difficult to isolate the effect of this privacy feature, as these platforms are still in good growth shape.
To enable/disable the option on your iPhone, go to Settings > Privacy > Tracking, then check/uncheck "Allow tracking requests from apps".