Out of all the offline notes apps on F-Droid, Quillnote is (in my opinion) the best. It supports markdown, so formatting documents will be easy.
Features:
- Markdown Support
- Notebooks
- Tags
- Task Lists
- Reminders
- File Attachment
- Photo Attachment
- Audio Attatchment
- Archive
- Sync with Nextcloud
- Pinning Notes
- Exporting Notes
- Backing Up Notes
- Sharing Notes
- Disabling Markdown
- Changing color of notes
- Hiding Notes
- Archiving Notes
Screenshots of the app:
