For any Android phone that can run Xposed, there's a module called MinMinGuard, that's quite effective in combatting verious in-app "native" ads, analytics and other sorts of spyware. As for browsers, there's Adblock Edge and µBlock readily available for Firefox, and few blocking apps (hosts-file-based and proxies) also exist (don't remember names, but at I think I've seen some on FDroid). Not much, but provides fairly good filtering and as easy as a few taps to get in a lot of cases.
