They could be referring to the app landscape too.

There's adblocking for that as well. Adaway works decently. Xposed can even do more.

I'm a bit more torn on this one. I've used Adfree Android before in this way but for the most part, if an app is good, I'll buy the full version. If it's something I just use a few times for a single purpose (and it's still useful), I'd like the dev to at least see some payment for it. If it's utter shit and full of obtrusive and annoying ads, I'd rather just uninstall it and give it a bad rating.

So root it and get a device-wide ad blocker?

The security implications and trust you would have to give to such a tool is frighting. The adverts seem like the lesser of two evils.

Are you saying that iOS9 has hooks for ad blocking in Apps? I doubt that.

No but typically applications on iOS are more likely to off a non-ad supported version. So perhaps they just mean in general.