[creichenbach]

A few years back I looked around what options exist for building a cross-plattform app. It should support mobile platforms (at least Android and iOS) as well as the web, properly.

The problem with cross-platform frameworks is that they either focus on a good mobile experience, and web becomes an afterthought, or vice versa, meaning mobile basically embeds a browser. Flutter is one of former; back then the web variant was in alpha and basically just a canvas that couldn't even adjust aspect ratio. Since web had priority for our project (accessability, reactive scaling, etc.), this was a no-go.

We ended up going with Ionic (which is basically Cordova with some components on top). The web experience is tweakable to a low level, and the mobile experience is acceptably good, even if not perfect. And we get to cover 3 platforms with the effort of building for ~1.2 apps (there is some platform-specific work involved still).

I'm not even sure if cross-platform is at all solvable in a perfect way, since the UI patterns between mobile and web are just too different.

[aatd86]

What UI patterns are so different if I may ask?

I have more experience with webdev but I can't seem to think of major differences in mobile.

[creichenbach]

Well, to have a perfect-ish solution, you'd have to build a framework with UI elements that map to native elements on each platform. Behavior and styling (e.g. positioning of elements) would need to be consistent, so you'd probably have to reduce functionality to the least common denominator for each possible dimension, or take the burden of implementing compatibility for A on platforms B and C. Web has a legacy of document-based components, while mobile is generally more interactive. There are overlaps nowadays, but staying within those boundaries would be a serious restriction.

On top of all that, you'd need a runtime that works on all platforms and is able to interact with native controls. I think React Native does something like that, but back then when I checked they did not have official web platform support (which is somewhat ironic, but I suspect technical difficulties too).

[aatd86]

Oh ok. So that's layouting that is different? (all else being accounted for)

[creichenbach]

Well, among other things. Native APIs are another thing that comes to mind, but those can be bridged more easily I suppose.