Apple is foraying into Google's cashcow in order to strangehold them by promoting the use of adblockers.
The detrimental effects of Adblockers would definitely afflict Google's revenue and profit when Adsense, Adwords and Youtube ads are all being filtered and blocked.
Other 3rd party web browsers adblocker plugin are also actively endorsing the use of their plugins to filter and block all kinds of intrusive ads online.
It would be very interesting to see to what extent these adblockers will do to Google's next few quarters of earnings and share prices.
Those stock analysts and institutional investors must be paying attention to threat of this magnitude.
A few important reading regarding this matter at below:
http://time.com/4052033/apple-iphone-ios-9-ad-blockers/
http://recode.net/2015/09/30/google-ads-boss-sridhar-ramaswamy-svp-ad-blocking-apple-ios/
https://au.news.yahoo.com/thewest/a/29654848/publishers-face-31b-ad-block/
Things could potentially get really ugly and out of hand to Google and other web companies like Facebook, Twitter, etc which wholly rely on ad revenues.