Detwinner
Samo Office
Secure office and productivity apps
Vnote
VNote is a Qt-based, free and open source note-taking application, focusing on Markdown now. VNote is designed to provide a pleasant note-taking platform with excellent editing experience.
Sigil
Sigil is a multi-platform EPUB ebook editor .
Paperwork
Paperwork will help you sort all your papers by turning them into searchable documents. It’s simple: just scan and forget. Looking for a specific paper? Just type in a few keywords and tada! You can search across your PDF files too!
Ghostwriter
Enjoy a distraction-free writing experience, including a full screen mode and a clean interface. With Markdown, you can write now, and format later.
Gnumeric
Gnumeric is an open-source spreadsheet program.
Calligra
Calligra Suite is an office and graphic art suite by KDE. It is available for desktop PCs, tablet computers, and smartphones. It contains applications for word processing, spreadsheets, presentation, vector graphics, and editing databases.
Pluma
Pluma is a text editor which supports most standard editor features. It also extends this basic functionality with other features not usually found in simple text editors.
Trilium
Trilium Notes is a hierarchical note taking application with focus on building large personal knowledge bases.