I'm more and more putting my words into words. My preferred format for this is markdown because I can put anything - outlines, todos, code, images, diagrams, attachments.
Bear is the best markdown editor, I have found so far.
It has excellent iOS and macOS apps. It is fast. Syncing works flawlessly. Its best feature is the tags. I have thousands of documents, and without them, I wouldn't be able to find anything.