There has been a growing concern on the Internet as many websites remain free because of ad revenue generated by simply the display of an ad on their page. This has generated some poor behavior such as "The Top Ten ____" (you fill in the blank) and the site will require you to load a new page just to see the next one. They get revenue each time the ad is displayed. If you choose to use an ad or content blocker, the ad won't load and they don't get the revenue. If the ads aren't even being requested, the page view can't be seen by the ad agency. Also the ad won't be consuming the data you're paying your ISP or mobile provider for. And the page loads faster. In some cases ten times faster. The other concern are the trackers. This is why if you happen to search for something like rocking chairs, you suddenly start to see ads on completely unrelated web pages for rocking chairs. The web sites are unrelated but they may be using the same ad service. Some website owners have gone as far as declaring that anyone that blocks their trackers and/or ads is a thief.
For me, this one feature of iOS 9 was enough to get me to install it on the day of its release instead of waiting for at least a couple of days.
Since Google generates all of their revenue with advertising, I'm not really surprised to see that there are no ad/content blockers within the default browser on Android. But I have been trying the Adblock Browser and Ghostery. Both are browsers that allow you to filter content and they are available in the GooglePlay Store. Both seem to have odd pauses when requesting a page which makes me wonder why.
Crystal was free yesterday but today it's 99¢. Peace it $2.99. uBlock Origin is free. Both Adblock Browser and Ghostery were free.