This! I hate when an app's GUI is following Windows-principles (if at all) and the macOS version is basically the same with a macOS theme slapped on top of it.

This! I hate when an app's GUI is following Windows-principles (if at all) and the macOS version is basically the same with a macOS theme slapped on top of it. About 10 years ago I've experimented with an early version of appcelerator Titanium for mobile app development. It was JavaScript but GUI rendering was transcoded to either Android-Java or Apple-ObjectiveC and the respective code was compiled natively (while running your main code via a JavaScript engine). With a bit of if-then-else you could make one app that compiled for both platforms and looked and felt native on both.