Buho is a note-taking application that lets you write the computer equivalent of sticky notes.
린우드 나비
Powerful, minimalistic, cross-platform, opensource note-taking app.
작가노트
Multiplatform application, currently available for linux, windows, macOS and android, which allows you to take notes in an intelligent way, you can record audio as you write, and listen to it again seeing what you have written for every second of the audio.
심플노트
The simplest way to keep notes
GTG
(GTG) is a personal tasks and TODO-list items organizer for the GNOME desktop environment
페더노트
Lightweight Qt5 Notes-Manager for Linux