The article below is an interesting read as I was unaware that Apple had enabled advert tracking on my IOS devices. They should have put that option under PRIVACY, but instead it's somewhat hidden away and defaults to be being enabled. The data is collected anonymously, but without requesting permission. http://www.theverge.com... I'm guessing that most people will have this monitoring enabled, without knowing about it. I changed the setting to "On", which is how to turn it "Off".
I switched it off when I set up my iPhone on purchase date. Also some apps have anonymous data collection enabled automatically. I switched that off also.
Exactly. Some apps have an option under IOS settings for preventing data collection. Yep. They use intentional obscuration.
But many apps also just do it My PDF reader for example phones home every time I open a new ebook. It sucks.