At least 419 million of the 1.9 billion smartphone users in the world use ad blockers, according to PageFair. Ad blockers are more popular in emerging markets where internet access is more expensive and much slower. As many as 36% of smartphone users in the Asia Pacific region use ad blockers on the mobile web, compared to 22% of smartphone users globally, the report said.

Several global websites that depend on advertising as their primary source of income have taken similar action.

Since December 2015, visitors on men’s magazine GQ have been getting popups that asked those who use ad blockers to either disable them or pay 50 cents to read an article. Forbes also prevents users with ad blockers from accessing its website.

Screen grab from Forbes website.

However, those publishers appear to be in a minority. According to some estimates, only 4% of large online publishers have taken “visible action” to stop visitors from using ad blockers.

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