The fastest, most data efficient, and most configurable

This is indeed, far and away, the best ad blocker for Safari on iOS right now. It is also one of the most configurable content blockers available. And, it will probably remain the best for a good while now — as long as it continues to be updated. Yes, comparing different performance tests and evaluations by various tech bloggers, currently, the next best are Adamant, and Silentium. (Purify is now fairly broken, and the developer hasn’t updated or otherwise responded to the issues for months. Crystal wasn’t all that great to begin with, and then also started taking money from advertisers to let ads through. Adguard is currently free, and fairly popular in some circles; but actually quite slow, and bloated, on iOS. Adblock Fast isn’t actually all that fast; and worse, it doesn’t save nearly as much mobile data as most other content blockers. Adblock Plus is slow, and takes money to let ads through. Norton by Symantec is slow.) [After Silentium, the up-and-coming, paid content blocker apps to keep an eye on, are Distilled, and then Refine.] I agree with another reviewer here, that Ka-Block!, and Mozilla’s "Focus by Firefox”, are probably among the best, and simplest, completely *free* ad blockers for Safari on iOS. However, I haven’t yet seen any comparative evaluations of their performance. The best long-term bet is possibly Focus; although it is not, and may never be, the best performer, and it doesn’t need to be. Regardless, this app, 1Blocker, is free for its essential functionality. If you wish to pay for its optional configurability features, which most other competing apps lack, it is still certainly well-worth that price in speed, and saved mobile data alone. If you need one now, get this one. Seriously.