I use a combination of UBO, PiHole and AdGuard on my mobile devices. Can't say I've seen an ad in the last year. Is this trying to solve an existing problem or speculating on where things could go in future?
I’m curious why you’re using 3 separate methods. Do you miss things with just one? AFAIK all 3 use similar block lists and are configurable. I’m building a pi-hole type solution for myself and essentially want all the filtering and blocking to happen at my firewall and not on my client (phone, laptop, tablet).
However you might end up using
1. pi-hole on router
2. Adguard as device level DNS
3. UBO on Firefox (android only)
It is possible but not recommended and wasteful. 1/2 and 3 is enough.