You can still buy a lifetime license. I got the family one (9 devices) for $170 a few months back, haven’t received any spam, and am really enjoying the extra features like userscript injection.
This is all on mobile. On desktop, I use ABP and uBlock Origin for ad blocking, and Tampermonkey for userscripts. But since none of those work on mobile unless you use specific browsers and avoid client apps altogether, AdGuard has been a pretty good replacement for me.