We reported a few days ago that Samsung's allowing its users to block ads through its mobile browser. Google's dashed those plans though as they pulled adblocking app AdBlock Fast from the Google Play Store. According to the app's developer, Rocket Labs, they got an email from Google Play saying the app breached section 4.4 of an agreement Android developers need to sign. The section says Google doesn't allow any activity that "interferes with, disrupts, damages, or accesses in an unauthorized manner the devices, servers, networks, or other properties or services of any third party including, but not limited to, Android users, Google or any mobile network operator."
By blocking ads, it's understood that this interferes with third-party services. It's worth noting that Google earns most of its revenue through advertising. And a lot of the web pages accessed through Samsung's browser run ads that make money for Google and other companies or organizations.
Source: The Guardian