TominLab WonderPen - WonderPen is a writing app for both professional and amateur writers.
Features
• Tree view, drag-and-drop to reorder.
• An easy-to-use text editor that supports Markdown.
• Supports full-screen mode, lets you focus on writing.
• Docs can be exported as Image, PDF, Word, HTML, etc.
• Support whiteboard mode, in which you can add any note, table, kanban and other information.
• Auto save while editing. You can backup all docs as a single file and restore from it later.
• Add memo for each doc.
• Focus on one node of the doc tree.
• Search in all docs.
• Darkmode support.
• Data can be backed up automatically, and import and export are supported.
Download: 
TominLab WonderPen 2.5.8.7566.rar - 180.7 MB