On my rooted Android tablet, I use AdAway with systemless host Magisk module as that is the true system-level option. Otherwise, the other options are to manually specify a DNS for your WiFi and mobile APN or to use a DNS app. Note that the DNS app will consume battery as it has to be activated for each redirect.
Otherwise, Adguard Home (or Pi-Hole) is best for home network adblocking.
There’s paid version of Blokada but free version works just fine.
If the device is rooted then adaway is fine otherwise adguard, you just have to prevent the system from killing it.
I use the cloudflare dns and it does remove most ads, but now websites seem to be coming up with new ideas, they usually open a new page with the link clicked and show a full page ad on the tab you’re currently viewing.
Was about to post, this setting works wonders, no ads in games or on any sites.
Have done it for all my family phones 
On samsung there is Adhell and no root is needed. It does more than that. Worth a look if you’re interested.
Dont know why it hasnt been working for me as well as it used to. I constantly see advert windows pop up when I click anywhere on specific websites.
Is your mobile 1nf3ct3d?
Have you installed any app from an outside source?, it may be laced with m4lw4r3 toppings.
It works like a charm for all my family phones.
Sorry, but why the leetspeak for infected and malware? That’s the first time I’ve ever seen anyone do that.
So he knows if his mobile is compromised, he has to look beyond adguard.
No such thing. The adblock works for most sites except a couple.
Now the sites are loaded with maybe some new form of ad codes designed to bypass adguard,
there are a few choices
-Wait for adguard to update their blacklist & include these sites
-Find alternative to those sites
-If the site is matter of life and death, Deal with it 
I also use Pixel 4a and use Blockada to block all ads.
Yes presently using Blockada and seems to do it’s work fine. I turn it on before browsing and then turn it off afterwards. It’s not the battery which is issue; it’s the persistent icon on the notification bar which annoys me. And thats why i turn it off. Lol 
I dont think that i have ever come across any such site. Please do let me know if there is any such website. Lol
Bank Sites, and mostly Govt Sites (Including the rusty old fart named Irctc), Indiarailinfo dot com, rest is well maybe, I’ll let the OP answer.
Lol. I am the OP in this case. 
I dont see any third party ads on bank sites. Govt sites… hmmm yes. there is no alternative. Agreed. But IRCTC is decent enough.
So please enlighten us, what exactly is the site which is annyong you with ads, for which the warriors of TE are facing defeat.
Na Na. Who said TE warriors faced defeat?
The AD war was over in first few posts itself. 
And I am using that method itself. And I am pretty happy with the result.
Share the address where we come to have our share of free booze & munchkins for the victory.
I’m surprised no one mentioned Firefox + ublock origin plugin. Not just that, there are many other plugins available (PrivacyBadger, HTTPS-everywhere, dark-mode themes which work on every web-page, etc).
I’ve been using Firefox on android ever since they had announced plugin support (Something which Chrome is still doesn’t support natively). With firefox anywhere you can continue browsing from phone and PC. Shared history is pretty nifty as well.