Use Firefox (or Mull or Fennec- both are forks) on Android.
I have Bromite too for times Firefox is being fucky.
On iOS unfortunately due to Apple’s (soon to be lifted) browser restrictions, the default Safari browser is basically as good as any other since Apple forces other browsers to basically just be reskins of Safari (forces webkit usage).
I do recommend Firefox Focus if you want stronger, Brave-like adblocking without using Brave obviously. Focus seems to block close to the same level as ublock origin + Firefox on a desktop. It’s barebones by design though, so not ideal for everyone.
I know Google/Mozilla are working on non-webkit Apple App Store approved browsers for next year when that law goes into effect (might not be available officially for NA users, not sure how that is gonna play out yet. Hopefully EU sues Apple for $100B for doing that if they do.) Hopefully that means official actual gecko based Firefox is coming fucking finally. Firefox with ublock is all I ever asked for. I’d even take Safari with actual ublock but unfortunately Apple is Apple, the annoying little fuckers.
F-Droid:
F-Droid is a robot with a passion for Free and Open Source Software (FOSS) on the Android platform. On this site you’ll find a repository of FOSS apps, along with an Android client to perform installations and updates, news, reviews, and other features covering all things Android and software-freedom related. https://f-droid.org/en/about/