GitJournal - Manage your Notes from any Git Repo.
Encrypted Notepad - Encrypted Notepad is a very simple to use application providing state of the art...
Category Tabs for Google Keep - Better organize your Google Keep Notes
Notebook PEA - Protects your private notes with a password.
Calendar Note by Enex - Calendar Note app allows users to view the calendar so they can write notes and memos according to dates to get alerts about tasks.
Paranoia Text Encryption - Paranoia Text Encryption encrypts text according to a choice of strong algorithms.