In reply to @aaron:matrix.org
That feature alone kept most of my group on matrix console beta until it was force killed.

Hi, an iOS developer and Riot iOS user here. Having done many rewrites/conversions of objc apps over the years, I thought I'd provide some findings. Sorry if some are obvious or have already been discussed:

• Of all the partial objc -> swift conversions (where part of the app/some files were converted) I have yet to find one that I'd consider successful. Since objc doesn't support all swift features, they often end up being almost literal conversions of the old code, since the swift interfaces have to be made with objc compatible patterns. There is little benefit since most of swift's benefits come from the new patterns that the language allows. Using those would basically require a second rewrite on top of it.
• I have yet to release a swiftui app to the store, but a lot companies I know are using it for new apps. Especially if they don't have an army of ios developers, since it's so much more efficient to develop. Yes, it's still buggy in places, but very usable in production apps if you're realistic about the capabilites and are wiling to write some parts in uikit (there is no way the chat screen could be made in swiftui, for example). I've also found it to be more performant in every scenario.
• If swiftui is not mature enough, I'd at least consider using Combine as much as possible. It allows for easier swiftui integration in the future, and it's really mature already. I'm using it even if the UI is uikit.
• Both do have the problem of being iOS 13 only. This is mostly a business decision of reach vs developer time.