Buho is a note-taking application that lets you write the computer equivalent of sticky notes.
Rerehua Linwood
Powerful, minimalistic, cross-platform, opensource note-taking app.
Tuhituhi
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.
Kuputuhi Maamaa
The simplest way to keep notes
GTG
(GTG) is a personal tasks and TODO-list items organizer for the GNOME desktop environment
Te Huruhuru
Lightweight Qt5 Notes-Manager for Linux