Also, Sorry for not linking apps I mentioned.
CherryTree - A hierarchical note taking application, featuring rich text and syntax highlighting, storing data in a single xml or sqlite file.
https://www.giuspen.com/cherrytree/
--
Joplin - An open source note taking and to-do application with synchronisation capabilities
https://joplinapp.org/
Google Keep - a web-based note-taking service developed by Google.
https://keep.google.com/
Extras which may interest you:
Zim - A Desktop Wiki - https://zim-wiki.org/
TreeSheets - Open Source, Free Form Data Organizer (Hierarchical Spreadsheet) - http://strlen.com/treesheets/
Also, Sorry for not linking apps I mentioned.
CherryTree - A hierarchical note taking application, featuring rich text and syntax highlighting, storing data in a single xml or sqlite file.
https://www.giuspen.com/cherrytree/
--
Joplin - An open source note taking and to-do application with synchronisation capabilities
https://joplinapp.org/
--
Google Keep - a web-based note-taking service developed by Google.
https://keep.google.com/
--
Extras which may interest you:
Zim - A Desktop Wiki - https://zim-wiki.org/
TreeSheets - Open Source, Free Form Data Organizer (Hierarchical Spreadsheet) - http://strlen.com/treesheets/