NOTE: this is a very old app, not really suitable for modern Android phones. It's listed here mainly for legacy / backwards compatibility reasons. It's still secure, just not user-friendly. You may need to use a long-press on one of the standard Android buttons (either the Task Manager, Home or Back) to bring up the app menu.
A very simple Notepad-like application which saves and loads encrypted documents, using a file format compatible with the desktop version available at http://www.sourceforge.net/projects/enotes .