This page collects good FOSS applications -- user-facing software. Please make sure software you add has current development and user communities - any size, just current! If software that meets this threshold later falls out of use, please keep it on the list for historical and reuse purposes, with the label (Not Current).
- Orca - screen reader and voice access.
- SITPLUS - eye tracking.
- Viacam - mouse replacement.
- Vinix - Ubuntu optimized for visually impaired users.
- jGnash - personal.
- GnuCash - personal financial management.
- LedgerSMB - SQL-Ledger fork.
- SQL-Ledger - first professional and now leading FOSS accounting app for businesses.
- KTooN - 2D animation.
 Association / Non-Profit Management
- CiviCRM - first and now standard FOSS app for association management, events, campaigns.
 Artificial Intelligence (AI)
- AliceBot - natural language chat bot.
- co.py.cat - python implementation of Douglas Hofstadter's copycat algorithm.
- Deeplearning4j - Java implementation including
- Mahout - Apache project for scalable machine learning.
- OpenCog - concerned with generic intelligence and the inter-related cognitive processes it entails.
- Tensorflow - Google's artificial intelligence software.
- Torch - machine learning framework with linear algebra, neural network, and energy-based model support, and packages for audio, computer vision, images, networking, signal processing, video, and others.
- Arduino Telescope ASCOM Driver - hardware controller standard.
- AIPS - Astronomical Image Processing System.
- GNU Radio - for radio astronomy.
- INDI - distributed control protocol for astronomical instrumentation.
- JSkyCalc - time and sky calculations.
- Observation Manager - astronomical observations logbook.
- PHD Guiding - intelligent auto-guiding.
- SGL Observatory Automation - automate an astronomical observatory.
- XEphem - sky charting.
- XmTel - telescope control software.
 Audio Editing
- Jack - audio connection.
- Ardour - digital audio workstation.
- FreeDownloadManager - multiple download methods.
- Time4Popcorn - Popcorn Github - movie streaming.
- qBittorrent - bittorrent client.
 Business Intelligence
- Pentaho - one of the first FOSS BI systems.
 CD/DVD Creation
 Church Management
- ChurchDB - management of families, integration with Google Maps.
- Asterisk - first and now standard Voice over IP (VoIP) management system.
 Computer Aided Design (CAD)
- BRL-CAD - solid modeling, interactive geometry editing, high-performance ray-tracing for rendering and geometric analysis, image and signal-processing.
- LibreCAD - standard open source CAD app, works with BRL-CAD.
Also see 3D modelling app "Blender" in Graphics section.
 Crowd Sourcing
- Ushahidi - dispersed information collection and mapping.
 Customer Relationship Management
- OpenCRX - with ticketing and issue management.
- vtiger - standard FOSS fork of original SugarCRM software.
- GNOME - most widely used Linux user interface, underlying Ubuntu.
- KDE - second most widely used Linux user interface.
 Desktop Publishing
- SCRIBUS - standard FOSS app for magazines, bulletins, handouts, posters.
 Development Environments
- Code::Blocks - Cross platform C, C++ and Fortran IDE, extensible, and configurable.
- Eclipse - standard FOSS integrated development environment (IDE), foundation supported by almost every major tech company, based in Ottawa, Canada.
- Lazarus - Delphi compatible cross-platform IDE with components ready for reuse, and a form designer to easily create complex GUI's and apps.
- MonoDevelop - Cross-platform support for quick development and porting of Microsoft C# and other .NET applications for Linux, Windows and Mac OS.
- Qt - Cross-platform application and UI framework for C++ and QML.
- SharpDevelop - Open source IDE for C#, VB.NET and Boo projects on Microsoft's .NET platform.
 Disaster Management
- OpenRelief - inexpensive drone controller.
- Tickets CAD - dispatch management and tracking system.
 Document Management
- Alfresco - one of the first and most widely used doc management systems, several commercial open source components but makes the list because they converted back to the GPL License.
- Nuxeo - standard FOSS doc management system from Europe, all FOSS components, scales from small to very large organizations..
 Ebook Readers
- Drupal Commerce - for Drupal websites.
- nopCommerce - asp.net based cart.
- Open For Business - one of the first FOSS e-commerce systems.
- oscommerce - one of the first FOSS e-commerce systems.
- RapidShop - shopping carts.
- Ubercart - integrates with Drupal.
- Virtuemart - integrates with Joomla.
- Course Builder - by Google.
- Moodle - one of the first and now most widely used FOSS education apps.
- VUE - unique capabilites, extraordinary visual mapping tool to help organize digital resources.
- Docear - unique solution to literature management, helps in integrating different tools/applications in single software (manages pdfs,references).
 Email & Calendar
- Evolution - widely deployed world wide by Novell in late 1990's, the standard enterprise level client.
- Thunderbird-Lightening - Mozilla (Firefox) supported client, most widely used individual FOSS client.
 Email Marketing
- OpenEMM - emails and campaigns with automated opt-out compliance.
 Emergency Services
- Open ISES Tickets - Information Systems for Emergency Services (ISES).
- Code-Aster - Civil and Structural Engineering finite element analysis and numeric simulation in structural mechanics.
- Adempiere - one of the very first FOSS ERP solutions.
- OpenERP - one of the most widely used.
- opentaps - one of the most widely used.
 File Compression
- 7-zip - support for gzip, zip, related formats.
 Flight Simulator
- Blender3D - 3D modeling.
- Cenon - vector graphics.
- DIA - first FOSS template tool, occasionally useful, now superseded by LibreOffice Draw, Gimp, Inkscape, and others.
- Gifsicle - create animated gifs.
- Gimp - standard FOSS bitmap editing application, extraordinarily powerful.
- ImageMajick - create animated gifs.
- Krita - painting and sketching.
- Inkscape - standard FOSS vector graphics application.
- Diagram Designer - Simple vector graphics editor for creating flowcharts, UML class diagrams, illustrations and slide shows.
- Graphite - scalable real-time graphing.
 Groupware (email, contacts, calendar, notes, tasks )
- eGroupWare - web-based.
- Group-Office - web-based
 Health / Medical / Dental
- Eclipse OHF - health framework.
- GnuMED - electronic medical records.
- OpenDental - dental application.
- OpenEHR - electronic health records.
- Open EMR - electronic medical records.
- OpenMolar - dental software.
- OpenTox - interoperable predictive toxicology framework.
- OSCAR - electronic medical records.
- VistA - electronic medical records.
 Human Resources (HR)
- OrangeHRM - first FOSS HR management software.
 Instant Messaging
- Pidgin - standard FOSS app for IM, can connect to all major networks.
- PHIRC (IRC)
 Inventory Management
 ISP Management
- Freeside - billing, CRM, trouble ticketing, network monitoring and provisioning for ISPs, VoIP providers and other industries.
 Issue Tracking
- Trac - standard (basic) FOSS issue tracking app, simple interface, customizable reports.
(See "Bug Tracking" software on "System Software" page for more sophisticated systems.)
 Label Printing
 Library Software
- Mathbuntu - learning software.
 Mind Mapping
- ArgoUML - UML modeling.
- Modelio - UML, BPMN, Java, XMI, HTML, Jython modeling environment.
- UMLet - text-based UML modeling.
- HandBrake - format conversions.
- Hugin - panorama photo stitcher.
- WhisperNote - portable encrypted HTML note.
 Office Suite
- Calligra Suite - Koffice spinoff.
- LibreOffice - standard FOSS office suite software, compatible with Microsoft Office, update of original OpenOffice.org.
 Optical Character Recognition (OCR)
- JavaOCR - suite of "pure" Java libraries with no external dependencies, small memory footprint, good for Android development. (Apache 2.0)
- ocropus - Python-based OCR package using recurrent neural networks, including scripts for ground truth editing and correction, measuring error rates, determining confusion matrices, and other features. (Apache 2.0)
- OpenKM - enterprise focus with modules such as version control, metadata, workflow, search, and user collaboration. (GPL 2)
- Tesseract - very accurate, works with Leptonica Image Processing Library in 60+ languages, developed by HP, now led by Google. (Apache 2.0)
 Password Managers
- EveryPass - a HTML5 based password manager that allows cross domain password management on modern, web enabled devices.
- KeePass - open source, light-weight and easy-to-use password manager for Windows, Linux, Mac OS X and mobile devices.
 PDF Viewers / Editors / Writers
- CC PDF converter - PDF printer.
- PDFCreator - PDF printer.
- Hugin - panoramic photo stitcher togetherer.
 Point of Sale
- Sozi - zooming presentation editor and player.
 Printing 3D
 Project Management
- GanttProject - Gantt charts, reads/writes MS project.
- Planner - simple interface, Gantt charts, resource allocation, cost roll-ups, HTML export, best basic tool.
- ProjectLibre - update of original OpenProj app, Gantt charts, resources, costing, read /write compatible with MS Project, best sophisticated tool.
- RedMine - web-based collaboration support for project teams.
 Real Estate
 Reporting / Charts / Graphs
 Resource Management
- Kazam - screen recording for screencasts.
 Search Engine
 Social Networking
- Diaspora - modeled on Facebook.
 Sound Editing
 Survey Software
 Terminal Emulation
- PuTTY - Telnet, SSH, xterm emulator.
 Timesheet & Time Tracking
- Timesheet Next Gen - spin-off of long-time Timesheet.php.
- Lyx - LaTeX based beautiful typesetting editor.
- TeXmacs - LaTeX based beautiful typesetting editor.
 Video Capture
 Video Players
 Video Conferencing
 Video Editing
- Avidemux - good video conversion, rotation tools.
 Virtual Desktop Clients
Also see Virtual Desktop Servers.
 Virtual Private Network
 Virtual World / Simulator
- Gaze Tracker - gaze tracker.
- OpenCV - computer vision libraries.
 Voice Calling
 Voice Recognition
 Website Analytics
- Analog - started in 1995, still being enhanced.
- AWStats - started 2000, command line tool.
- Piwik - includes marketing and related analysis.
- Webalizer - fast C code, HTML reports.
- W3Perl - all Perl, email and HTML and PDF reports.
 Web Browser
- Firefox - standard FOSS app until Chrome took more user share, traces lineage as a descendent of the first widespread browser Netscape.
- Chrome - Google supported browser, very fast, portal to bring users into other (non-FOSS) Google services.
 Web Conferencing
- BigBlueButton - standard FOSS conferencing app for education.
- DimDim - one of the first FOSS conferencing apps.
- Openmeetings - a widely supported Apache project.
- WebHuddle - one of the first FOSS conferencing apps.
 Website Content Management Systems (CMS)
- Drupal - most widely used FOSS content management system for complex sites, many themes and plugins.
- Joomla - second most widely used FOSS content management system.
 Website Development
- Amaya - original browser supported by creator of web, Tim Berners-Lee, with his vision of always being able to both view and edit any page in the same app.
- Bluefish - editor.
- BlueGriffon - editor.
- DRKSpiderJava - Multiplatform Website crawler and link checker.
- WordPress - standard and most widely used FOSS website software, large set of templates, support for blogging, discussions, forums.
- MediaWiki - original and same software that runs Wikipedia.