The iOS version of Focus is implemented as a content blocker, and you can use it across the system.
There's also the VPN option. PIA, for example, comes with its own system ad-blocker (MACE) although it's nowhere as good as Adguard Pro (which allows you to use custom DNS server).
I very seldomly watch live ad supported video. I have ad free Hulu. For the two networks that aren't on Hulu - CW and CBS, I watch VOD from them via Plex. Because of the way that the Plex channels work, they skip the ads.