LibreOffice is a powerful office suite.  Its clean interface and
  feature-rich tools help you unleash your creativity and enhance your
  productivity.  LibreOffice includes several applications that make it the most
  powerful Free and Open Source office suite on the market: Writer (word
  processing), Calc (spreadsheets), Impress (presentations), Draw (vector
  graphics and flowcharts), Base (databases), and Math (formula editing).
      LibreOffice supports opening and saving into a wide variety of formats, so
  you can easily share documents with users of other popular office suites
  without worrying about compatibility.
    

LibreOffice

Create, view and edit text documents, spreadsheets and presentations of any size and complexity. Work on documents of most popular formats: DOCX, ODT, XLSX, ODS, CSV, PPTX, ODP, etc. Deal with multiple files within one and the same window thanks to the tab-based user interface.

ONLYOFFICE Desktop Editors

Unofficial Microsoft Teams client for Linux using Electron.It uses the Web App and wraps it as a standalone application using Electron.

teams-for-linux

Unofficial Microsoft Teams client for Linux using Electron

Obsidian is a powerful knowledge base that works on top of a local folder of plain text Markdown files. In Obsidian, making and following connections is frictionless, and with the connections in place, you can explore all of your knowledge in the interactive graph view. Obsidian supports CommonMark and GitHub Flavored Markdown (GFM), along with other useful notetaking features such as tags, LaTeX mathematical expressions, mermaid diagrams, footnotes, internal links and embedding Obsidian notes or external files. Obsidian also has a plugin system with 20+ supported plugins to expand its capabilities.
      The documentation can be accessed by opening the demo vault that is shipped in Obsidian.
      Obsidian will always remain free for personal use, no account or license is required for qualifying use cases described in the End User License Agreement. However, commercial users should purchase a license on Obsidian's website. Users also have the option to purchase a Catalyst license to get early access to insider builds and support the development. Additionally, Obsidian offers an optional paid hosting service for your notes. Details about this optional hosting service can be found on the Obsidian website.
      This distribution is currently in beta and not officially supported by the Obsidian team
      There is now experimental Wayland support that can be enabled with OBSIDIAN_USE_WAYLAND=1 in Flatseal
      GPU acceleration can be disabled if necessary by setting OBSIDIAN_DISABLE_GPU=1 and/or OBSIDIAN_DISABLE_GPU_SANDBOX=1 in Flatseal
      pdflatex support in pandoc currently requires installing the org.freedesktop.Sdk.Extension.texlive SDK
      Note: Regular users should disable "Automatic Updates" within Obsidian as public release updates are handled by Flatpak itself. Insiders should keep this enabled to receive insider builds, as those will not be made available on Flathub.
      This flatpak goes into great lengths to provide a nice experience for end users. In order for the Git plugin to work it requires permission to the ssh-auth socket (--socket=ssh-auth). It also exposes the home directory in the sandbox (required for Drag and Drop operations). If you don't use the Git plugin you can disable the ssh-auth socket permission, e.g. using Flatseal. You can also remove access to the home directory if you want and the flatpak will continue to work, albeit with reduced functionality. In case you do remove access to the homedir, note that in order for things to not break for the Git plugin, --persist=.ssh flag has been passed and a bind mount to ~/.var/app/md.obsidian.Obsidian/ is created by flatpak, allowing that location to be used for persistent data (but your home directory's .ssh remains unaccessible)
    

Obsidian

Contacts keeps and organize your contacts information. You can create, edit, delete and link together pieces of information about your contacts. Contacts aggregates the details from all your sources providing a centralized place for managing your contacts.Contacts will also integrate with online address books and automatically link contacts from different online sources.

Contacts


      Thunderbird is a free and open source email, newsfeed, chat, and
      calendaring client, that’s easy to set up and customize. One of the core
      principles of Thunderbird is the use and promotion of open standards -
      this focus is a rejection of our world of closed platforms and services
      that can’t communicate with each other. We want our users to have freedom
      and choice in how they communicate.
    
      
      Thunderbird is an open source project, which means anyone can contribute
      ideas, designs, code, and time helping fellow users.
    
    

Thunderbird

Thunderbird is a free and open source email, newsfeed, chat, and calendaring client

A document viewer for the GNOME desktop. You can view, search or annotate documents in many different formats.Evince supports documents in: PDF, PS, EPS, XPS, DjVu, TIFF, DVI (with SyncTeX), and Comic Books archives (CBR, CBT, CBZ, CB7).

Document Viewer

Document viewer for popular document formats

GNOME Calendar is a simple and beautiful calendar application designed to perfectly fit the GNOME desktop. By reusing the components which the GNOME desktop is built on, Calendar nicely integrates with the GNOME ecosystem.We aim to find the perfect balance between nicely crafted features and user-centred usability. No excess, nothing missing. You’ll feel comfortable using Calendar, like you’ve been using it for ages!

Calendar

Adobe Reader software is the official Adobe software for viewing, printing, and annotating PDF documents.NOTE: This software is unmaintained by the vendor and may contain security vulnerabilities.NOTE: This wrapper is not verified by, affiliated with, or supported by Adobe.

Adobe Reader

WPS Office including Writer, Presentation and Spreadsheets, is a powerful office suite, which is able to process word file, produce wonderful slides, and analyze data as well. It is deeply compatible with all of the latest Microsoft Office file formats. It can easily open and read the documents created with Microsoft Office.NOTE: This wrapper is not verified by, affiliated with, or supported by Kingsoft Office Corporation

WPS Office

Master PDF Editor is straightforward, easy to use application for working with PDF documents equipped with powerful multi-purpose functionality. With Master PDF Editor you can easily view, create and modify PDF documents. The application enables you to merge several files into one, split a source document into multiple documents, and also to comment, sign and encrypt PDF files.NOTE: This wrapper is not verified by, affiliated with, or supported by Code Industry.

Master PDF Editor

View, create, modify, sign, scan, OCR and print PDF documents

calibre is the one stop solution to all your e-book needs.You can use calibre to catalog your books, fetch metadata for them automatically, convert them from and to all the various e-book formats, send them to your e-book reader devices, read the books on your computer, edit the books in a dedicated e-book editor and even make them available over the network with the built-in Content server. You can also download news and periodicals in e-book format from over a thousand different news and magazine websites.

calibre

The one stop solution to all your e-book needs

Rnote is a vector-based drawing app for sketching, handwritten notes and to annotate documents and pictures.Disclaimer: The file format is still unstable. It might change and break compatibility between versions.

Rnote

Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, can be copied, tagged and modified either from the applications directly or from your own text editor. The notes are in Markdown format.Notes exported from Evernote via .enex files can be imported into Joplin, including the formatted content (which is converted to Markdown), resources (images, attachments, etc.) and complete metadata (geolocation, updated time, created time, etc.). Plain Markdown files can also be imported.The notes can be synchronised with various cloud services including Nextcloud, Dropbox, OneDrive, WebDAV or the file system (for example with a network directory). When synchronising the notes, notebooks, tags and other metadata are saved to plain text files which can be easily inspected, backed up and moved around.The application is available for Windows, Linux, macOS, Android and iOS (the terminal app also works on FreeBSD). A Web Clipper, to save web pages and screenshots from your browser, is also available for Firefox and Chrome.

Joplin

A free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks.


   Okular is a universal document viewer developed by KDE. Okular works on multiple platforms, including but not limited to Linux, Windows, Mac OS X, *BSD, etc.
  
      Features:
      
        Supported Formats: PDF, PS, Tiff, CHM, DjVu, Images, DVI, XPS, Fiction Book, Comic Book, Plucker, EPub, Fax
        Sidebar with contents, thumbnails, reviews and bookmarks
        Annotations support
      
    

Okular

PDF Arranger is a small application, which helps the user to merge or split pdf documents and rotate, crop and rearrange their pages using an interactive and intuitive graphical interface.It is a frontend for pikepdf.Het is een frontend voor pikepdf.

PDF Arranger

PDF Merging, Rearranging, Splitting, Rotating and Cropping

Need to safely store all of your important documents, photos, songs, and files? Easy! With this app you can use the internet to save everything that’s important to you. You can then access those files from any computer that has an internet connection. Use this service to backup your files, share photos or collaborate on a project by sharing a Dropbox folder with whomever you’d like. Create a free account and start saving and sharing today!  ** Requires internet.NOTE: This wrapper is not verified by, affiliated with, or supported by Dropbox, Inc.

Dropbox

Foliate is a simple and modern GTK eBook viewer.Features include:Two-page view and scrolled viewCustomize font and line-spacingLight, sepia, dark, and invert modeReading progress slider with chapter marksBookmarks and annotationsFind in bookQuick dictionary lookup

Foliate

Much faster, more beautiful and more powerful.Features include:Features come with Whatsapp webMultiple usersIcon in systray with different icon if there is new messagesCustomizable Systray iconsSystem style (light and dark)Fullscreen modeBackground runningSpellcheckerDrag and dropWork area notificationsPersonalized window decorationShortcuts for the main optionsWhat doesn't include: Video calls and On-call calls

ZapZap

Zotero [zoh-TAIR-oh] is a free, easy-to-use tool to help you collect, organize, cite, and share your research sources.NOTE: If your Zotero folder is not located inside your home directory (~/) and is outside your xdg-user-dirs, please grant permission to access that folder by the flatpak-override command (usage: "flatpak override --user --filesystem=/PATH/TO/ZOTEROFOLDER org.zotero.Zotero").NOTE: This wrapper is not verified by, affiliated with, or supported by the Zotero project.

Zotero

Collect, organize, cite, and share research

Evolution is a personal information management application that provides integrated mail, calendaring and address book functionality.
      Evolution supports a wide range of industry standard data formats and network protocols for information exchange, with an emphasis on standards compliance and security. Evolution can also integrate smoothly with Microsoft Exchange by way of the “Exchange Web Services” (EWS) extension.
    

Evolution


      Betterbird is a soft-fork of Mozilla Thunderbird. Simply better.
    
    

Betterbird

Betterbird is a soft-fork of Mozilla Thunderbird. Simply better.

Xournal++ is a hand note taking software written in C++ with the target of flexibility, functionality and speed. Stroke recognizer and other parts are based on Xournal Code, which you can find at sourceforge. It supports Linux (e.g. Ubuntu, Debian, Arch, SUSE), macOS and Windows 10. Supports pen input from devices such as Wacom Tablets.Xournal++ features:Supports pressure senstive styluses and digital pen tables (e.g. Wacom, Huion, XP Pen, etc. tablets)Paper backgrounds for notetaking, scratch paper, or whiteboardingAnnotate on top of PDFsExport to a variety of formats including SVG, PNG and PDF, both from the GUI and command lineDifferent drawing tools (e.g.pen, highlighter) and stroke styles (e.g. solid, dotted)Shape drawing (line, arrow, circle, rectangle, spline)Fill shape functionalityShape resizing and rotationRotation and grid snapping for precise alignment of objectsInput stabilization for smoother writing/drawingText tool for adding text in different fonts, colors and sizesEnhanced support for image insertionEraser with multiple configurationsLaTeX support (requires a working LaTeX installation) with customizeable templateSidebar with Page Previews with advanced page sorting, PDF Bookmarks and Layers (can be individually hidden/edited)Allows mapping different tools/colors etc. to stylus/mouse buttonsCustomizeable toolbar with multiple configurations, e.g. to optimize toolbar for portrait/landscapePage Template definitionsBug reporting, autosave, and auto backup toolsAudio recording and playback alongside with handwritten notesMulti language support (over 20 languages supported)Plugins using Lua scripting

Xournal++

BlueMail by Blix is a free, beautifully designed, universal email app, capable of managing an unlimited number of mail accounts from various providers, allowing for smart push notifications and group emailing while enabling personalization across multiple email accounts. The BlueMail app connects directly to your mail server and is the perfect replacement for your stock email app.NOTE: This package is not verified by, affiliated with, or supported by Blix Inc.

BlueMail

Ideas Grow on Trees.Xmind is a full-featured mind mapping and brainstorming app. Like a Swiss Army Knife for your brain, spark creativity and improve thinking skills. 100+ million installations on the planet.

Xmind (2022)

Todoist is used by 20 million people to organize, plan, and collaborate on projects, both big and small.Use Todoist to:Capture and organize tasks the moment they pop into your head.Remember deadlines with reminders and due dates.Build lasting habits with recurring due dates like "every Monday".Collaborate on projects by assigning tasks to others.Prioritize your tasks with priority levels.Track your progress with personalized productivity trends.Integrate your tools like Gmail, Google Calendar, Slack, Amazon Alexa, and more.Available on any device, Todoist will quickly become your hub for getting work and life organized.Happy organizing!•Questions? Feedback? Visit get.todoist.help or reach out on Twitter at @todoist.NOTE: This wrapper is not created by, affiliated with, or supported by Doist.

Todoist: To-Do List & Tasks

“The best to-do list app right now” - The Verge


			Cryptomator provides transparent, client-side encryption for your cloud. Protect your documents from unauthorized
			access. Cryptomator is free and open source software, so you can rest assured there are no backdoors.
		
      
			Cryptomator encrypts file contents and names using AES. Your passphrase is protected against bruteforcing attempts
			using scrypt. Directory structures get obfuscated. The only thing which cannot be encrypted without breaking your
			cloud synchronization is the modification date of your files.
		
      
			Cryptomator is a free and open source software licensed under the GPLv3. This allows anyone to check our code. It
			is impossible to introduce backdoors for third parties. Also we cannot hide vulnerabilities. And the best thing
			is: There is no need to trust us, as you can control us!
		
      
			Vendor lock-ins are impossible. Even if we decided to stop development: The source code is already cloned by
			hundreds of other developers. As you don't need an account, you will never stand in front of locked doors.
		
    

Cryptomator

Multi-platform client-side encryption tool optimized for cloud storages

With its simple, elegant and adaptive interface, this manga reader allows you to search, sort and read all your favorite manga with ease.Why you will love Komikku?Online and offline reading from dozens of serversSupport for locally stored manga (in CBZ or CBR formats)RTL, LTR, Vertical and Webtoon reading modesSupport several types of navigation: keyboard arrow keys, right and left navigation layout via mouse click or tapping (touchpad/touch screen), mouse wheel, 2-fingers swipe gesture (touchpad), swipe gesture (touch screen)Categories to organize your libraryAutomatic update of mangaAutomatic download of new chaptersReading historyLight and dark themes

Komikku

GnuCash is a program for personal and small-business financial-accounting.Designed to be easy to use, yet powerful and flexible, GnuCash allows you to track bank accounts, stocks, income and expenses. As quick and intuitive to use as a checkbook register, it is based on professional accounting principles like double-entry accounting to ensure balanced books and accurate reports.With GnuCash you can (but are not limited to):Keep track of your day to day personal income and expensesManage your stock, bond and mutual fund accounts with easeKeep your small business' accounting up to dateCreate accurate reports and graphs from your financial dataSet up scheduled transactions to avoid repeated data entryExchange by CSV/FinTS(former HBCI) or import SWIFT-MT9xx/QIF/OFX data including Transaction MatchingPerform financial calculations, such as a loan repayment

GnuCash

Manage your finances, accounts, and investments

Focus on your writing with a clean, distraction-free markdown editor.Features:An UI tailored to comfortable writingA distraction-free modeDark, light and sepia themesEverything you expect from a text editor, such as spellchecking or document statisticsLive preview of what you writeExport to all kind of formats: PDF, Word/Libreoffice, LaTeX, or even HTML slideshows

効率化