What I like about Kotlin Multiplatform (KMP) vs Flutter is that KMP is not a framework. For instance, I can write a KMP library and a "pure" Android or iOS app can pretend it is a "pure" Android/iOS library.

That is, pure native apps, can integrate KMP libraries. They cannot integrate Flutter libraries.

In other words, if I write a KMP library, I can ship it for multiple platforms and developers can use it in their Flutter project, or in their pure Android/Kotlin project, or in their pure iOS project.

There is no right way :)

SwiftUI is good, albeit not without issues, as long as you tolerate them. The same is true for any approach. My most recent app was built in SwiftUI because I have been using React Native in my professional work for so long I wanted a change of scenery.

Each approach has its issues, and it all boils down to a matter of preference and which tradeoffs are appropriate for the project.

I wonder what experts think of this other option: going fully native for one platform then vibe-porting it to others.

Flutter is not the "right way", due to the nature of Flutter being a lousy reimplementation of a UI frameworks.

I know people would dismiss this, but I'm going to try to make the case for Qt - I'm currently converting my note-taking app to mobile and it's going very well.

I developed a complicated app in Flutter and it’s one of the best engineering decisions I made. Flutter is great.

Flutter has been a great success for us.

Define right, it’s hard to replicate the native UI especially Liquid Glass on iOS because it’s rendering everything using its own rendering engine, making it hard to feel right on iOS. I have also seen a lot of companies move away from flutter to either native or React Native.