WinUI

WinUI was initiated in 2018,  tried WinUI for the first time finally in December 2023 in an attempt to migrate from Uno UWP to Uno WinUI. It was so flaky and lacking many UWP functions that I stopped quickly.

WinUI may be good for some experiments or fun, not serious production apps.

This GitHub discussion says all about the poor state of WinUI. This Reddit comment is also informative. Microsoft itself shows muted enthusiasm in WinUI.

Visual Studio 2022 does not support the creation of app bundles that can be uploaded to the Microsoft Store to update UWP apps. So, if you have an established UWP app in the Microsoft Store, and port the code to WinUI with Visual Studio 2022. you cannot create a package that can be used to update the app in the store.

Visual Studio 2026 finally had the ability to generate app bundles in late 2025, so I gave WinUI another shot. It was disastrous, and wasted a few days of my time. I ported a large utility library to WinUI, then migrated a very simple app from UWP to WinUI. Everything worked flawlessly when the app was deployed from VS2026, for both the debug version and the release version. To my complete surprise, the app downloaded from the Microsoft Store has all sorts of problems (crashing upon opening, working for the first run but crashing for subsequent runs, strange exceptions...). Since it crashed upon start, you cannot attach VS to its process. Debugging the store version is a major nuisance. One has to make a side loading package to simulate the store version. This is absolutely a show stopper. Even if you could make it work after the migration from UWP, you would always worry that any changes you made to the app might break the store version, even if everything worked flawlessly with the VS-deployed version.