Mobile Safari supports content-blocking extensions.

https://developer.apple.com/videos/play/wwdc2015/511/

Presumably there's something similar on Android.

Is there maybe an ambiguity between "blocking mobile ads in apps" and "blocking web ads in a mobile browser"? The former might require lower-level tampering, while the latter might just require using a mobile browser that blocks ads or can run extensions.

I use uBlock Origin on Firefox for Android without root.

Not on iOS, presumably since Apple isn't making their money from advertising.

They would have no reason not to sell the feature of "better user experience" from blocking ads / trackers.

I use https://itunes.apple.com/us/app/purify-block-ads-and-trackin...

On the iPhone you can block ads on non-rooted phones! It's awesome.

I use AdBlock Fast, but I say "use" casually since it's just an app you install and you're done with it. I never actually opened it after installing it months ago.

No more ads ever on mobile.

Local VPN-based solutions do the job without root. Check out AdClear, Adguard, etc.

On Samsung with Knox (surely S6 and later, maybe S5?), AdHell works just like if it had root. Best thing ever.

I used to use a VPN solution on Android without root, but I eventually switched from Chrome to Brave, which has worked quite well.

https://brave.com/

In China, some routers provide the optional feature of blocking ads by domain names.