@cartman82 said in Cross platform desktop app:
Python, usually not there on Windows.
That's what things like PyInstaller is for. I use it for a Python program I'm working on, which uses Tkinter/ttk for the UI; it lets me get single-file executables on both Linux and Windows in less than 10MB each. (On OS X, you'd normally want to go for an .app folder there, and the builds are a bit larger).
If you want to use another UI framework, that should still be possible (even as single-file executables; PyInstaller has pretty good compatibility there), but of course the EXE size is likely to grow.
You can even cheat a bit and only compile a stub which then loads Python code directly from .py files, if that's a thing you want. (The things you're using will have to be available in the built executable, of course, so you might have to import some extra libraries in that stub loader to get that to work.)