This is—without a doubt—the best ad blocker for iOS. The rules are insanely customizable, but simply installing and activating 1Blocker will ensure that you don't see ads on iPhone or iPad ever again, which makes it both very simple for *everyone* and very powerful for more advanced users. The developers are also responsive when questions are asked.
If you used the first version of 1Blocker (now called "Legacy") and are wondering if you should pay to upgrade to this latest version—do it. It's worth every penny, and I'm really excited about the future of this app.