It works in conjunction with a VPN -- VPN's encrypt your traffic and mask your IP, but they don't stop trackers which can identify you based on your PC, your browser, existing cookies, settings, tracking pixels, the list goes on
AntiTrack Premium obfuscates your true "digital fingerprint" as well as stops tracking attempts and targeted advertising (everything from analytics scripts to advertising cookies) and reports on how many times attempts were blocked.
However, it's not an ad-blocker or a cookie blocker. It's more of a "spoofer." The nice thing is that it protects your online privacy without breaking the Internet
A lot of extensions that block scripts will do this effectively but render a lot of websites at least ugly, sometimes unusable. And of course there's sites with ad-blocker paywalls.
So in my opinion, it's a good companion to SecureLine VPN.
I think the official page sums it up pretty well too:
https://www.avast.com/en-us/antitrack
