GUI
GTK and Tauri are probably the only options which can be described as production-ready without caveats. The Rust native options are usable for simple projects but are all still quite incomplete.
See the relevant section in blessed.rs⮳
Tauri
Tauri⮳ is an app construction toolkit that lets you build software for all major desktop operating systems using web technologies. It is similar to Electron.
egui
egui⮳ is an easy-to-use immediate mode GUI that runs on both web and native. egui aims to be the best choice when you want a simple way to create a GUI, or you want to add a GUI to a game engine.
Other GUI frameworks
(github) is a cross-platform GUI library for Rust, inspired by Elm.
(github) is a data-first Rust-native UI design toolkit (experimental).