This marks the first time that Opera uses the WebKit rendering engine - in fact, as far as I know, it's the first time the company uses a rendering engine that isn't Presto, or an offshoot or precursor thereof. Opera states that in roder to stay relevant, it has to have a full-fledged, modern browser on both iOS and Android. While Android doesn't enforce a rendering engine, iOS does (with additional limitations, since only Apple itself is allowed to use Nitro, iOS' fast JavaScript engine), and because of this, Opera is forced to use WebKit for the iOS version, at which point they might as well use it on Android as well.

This allows the Opera engineers to focus on the user interface, and that's where the innovation lies. Opera's goal is to put the website content front and centre, eliminating virtually all of the user interface elements in favour of gestures to perform basic UI functions.