CherryTree is an hierarchical note taking application, featuring rich text and syntax highlighting, storing data in a single xml or sqlite file.

Google Keep is a cloud based note taking application.

Microsoft OneNote is a digital note taking and sharing app from Microsoft.

Notezilla is a sticky notes app for Windows.

Guide is an application that allows you create documents ("guides") which inherently have a tree (which you can modify as you please) and text associated wit…

Evernote is a note taking application which keeps the notes taken in sync across all platforms using its cloud infrastructure.

Joplin is an open-source free note taking and to-do application.

NoteLedge note-taking and management solution.

ResophNotes is a fast note writing tool and a Simplenote client on Windows.

ThinkComposer is a flexible visual tool, which allow users to create enriched diagrams based on their domain of knowledge.