According to this story in Advertising Age, about one fifth of Apple iOS users have taken advantage of the Limit Ad Tracking setting, which opts them out of targeted advertising on their mobile devices.  “About 18 million iPhone and iPad users in the U.S., roughly 20% of the total, have used LAT to explicitly opt out of targeted advertising, according to a report released Wednesday by app marketing platform Adjust.”  It doesn’t turn off advertising, it just means you are more likely to see some random ad instead of one based on your past behavior.

How to do it

The article doesn’t show the readers how to find this option – which is understandable in a publication devoted to advertising. But if you would just as soon not to be tracked by advertising networks (you’ll still probably be tracked by the government), go to

Settings >Privacy> Advertising

and either turn on the option to “Limit Ad Tracking” or reset your advertising identifier, to start the tracking over again. (I guess if you’ve just been searching for something for which you don’t want to be seeing ads.)