Lifeograph is an off-line and private journal and note taking application for Linux desktops and Android. It offers a rich feature set presented in a clean and simple user interface.
RoboJournal is a Qt/C++ cross-platform diary and jounraling editor. It stores tagged entries in MySQL/MariaDB or SQLite databases (PostgreSQL planned). It runs and is prepackaged for Windows and Linux systems, comes with extensive help, wizards, search and archiving functions.