Buho is a note-taking application that lets you write the computer equivalent of sticky notes.
Borboleta Linwood
Aplicativo de anotações poderoso, minimalista, multiplataforma e de código aberto.
Writernote
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.
SimpleNote
A maneira mais simples de manter as anotações
GTG
(GTG) is a personal tasks and TODO-list items organizer for the GNOME desktop environment
PenaNotas
Lightweight Qt5 Notes-Manager for Linux