is it doing its own ad blocking or is it doing ad blocking as a safari ad block extension? There is a very specific high-performant ad block mechanism in iOS now.

If it's anything like the ones I looked at a while back, it goes through a proxy to strip the ads. So all of your web browsing goes through a 3rd party. I'm no technical wiz on such things, but I can't think of how else it could work without being an Apple-approved Safari extension.

It could run a local proxy on the device itself, perhaps. I know iPhone apps can expose HTTP servers to other devices on WiFi for file sharing, so I wouldn't be surprised if you can expose it to localhost too.

Mm, good point, and given that I actually wrote a baby web server for serving up docs a long time ago, I'm disappointed that it didn't occur to me. In fact, I wonder why more don't do that. All of the ones I looked at (and it's hardly an all-encompassing list) seemed to do it through a proxy that the dev hosted.

It's a browser shell which has been doing ad blocking for over a year, so it would probably do it's own thing.

> it blocks ads just fine.

In Safari? Working as intended. In Chrome or Firefox? Unexpected (according to their link).

If the ad blocking is built-in to the browser, it should work fine. It's the new content-blocking plugins that only work in Safari.

Apple doesn't let custom browsers use anything other than their WebView component for rendering, and WebViews are pretty limited when it comes to modifying page content.

The new Safari View Controller can use content blockers, but it basically opens a Safari window over the top of the app you're viewing (doesn't adhere to the app's design at all).