Source: http://www.bloombergview.com/articles/20...

Besides, Google's operating system, Android, has long allowed ad blocking. This has often meant installing AdBlock Plus, the software developed by the German company Eyeo. It has about 50 million users on computers and mobile devices and a business model based on charging site owners to put them on a "whitelist" as "acceptable  ad"  providers. Apart from paying, these companies must to commit to some simple rules: no pop-ups, no sound, no self-launching videos -- in short, none of the aggressive formats Web users have come to hate. (Users can block the "acceptable" ads, too).

PageFair suggested Google may be Eyeo's biggest customer. According to PageFair, Google may be losing $6.6 billion in annual revenue due to ad blocking; being whitelisted allows it to save about $3.5 billion.

Eyeo is not happy with Apple's decision to offer ad blocking. It has warned that if the Apple-made extension isn't powerful enough -- and Eyeo is blocked from developing ad-blocking software for iOS -- "that could mean the end of ad blocking on Safari." That's probably sour grapes. If Apple's mobile devices become off limits because only the proprietary content blocking system is allowed, Eyeo will lose a great opportunity to expand into the Apple universe. Apple, meanwhile, will still collect ad revenue from its iAds program, which works inside applications, not in the browser, so the new extension wouldn't block it.

With giants such as Apple and Google involved, it's clear that ad blocking shouldn't be discounted. In the second quarter of 2014, there were 144 million active ad-block users globally, 70 percent more than a year before, according to a PageFair report. That's less than 5 percent of the global Internet population, but in the U.S., 27.6 percent of Internet users opt for an ad-free experience, and some European countries, notably Poland and Sweden, are approaching that level. Millennials are the biggest ad haters: 41 percent of U.S. Internet users between 18 and 29 kill ads.