Free Open Source To-Do Lists Software

A mind mapper, and at the same time an easy-to-operate hierarchical editor with strong emphasis on folding. These two are not really two different things, just two different descriptions of a single application. Often used for knowledge and content management.

Joplin is a free and open source note-taking and to-do application that can handle a large number of notes in Markdown format, organize them into notebooks and synchronize them with various cloud services. All notes can also be copied, tagged, searched and modified directly from the app or through your own text editor. Notes that are exported from Evernote can be imported into Joplin, be it formatted content, resources, complete metadata or plain Markdown files. When notes are synchronized with cloud services, notebooks, tags and other metadata can easily be moved, inspected or backed up as plain text files. Supported cloud services include Nextcloud, OneDrive, Dropbox and WebDAV. Joplin is available for Windows, Linux, macOS, iOS and Android, with three types: desktop, mobile and terminal. All of them have similar user interfaces and can be synchronized with each other.

PNotes is light-weight, flexible, skinnable manager of virtual notes on your desktop. It supports multiple languages, individual note's settings, transparency and scheduling. Absolutely portable as well - no traces in registry. PNotes.NET edition requires .NET framework 4 Client Profile

Task Coach - Your friendly task manager. Task Coach is a free open source todo manager. It grew out of frustration about other programs not handling composite tasks well. In addition to flexible composite tasks, Task Coach has grown to include prerequisites, prioritizing, effort tracking, category tags, budgets, notes, and many other features. However, users are not forced to use all these features; Task Coach can be as simple or complex as you need it to be. Task Coach is available for Windows, Mac OS X, and GNU/Linux; and there is a companion iOS app.

Notes is an open source, cross-platform note-taking application. Write down your thoughts with ease, and always have them with you with this simple, streamlined app.

WikidPad is a wiki-like notebook for storing your thoughts, ideas, todo lists, contacts, or anything else you can think of to write down.

Collabtive is web based collaboration software. It is an Open Source alternative for proprietary tools like Active Collab or Basecamp. Features include: Projects, Instant Messenger, Tasks, Files, Timetracking, Multilanguage, Basecamp import

Ferdi is a desktop app that helps you get organized and work more efficiently by having all of your favorite apps in one application. Ferdi is based on Franz, a messaging browser that combines all messaging services into one application, but Ferdi offers a whole lot more. Ferdi puts all your web apps in one place, has "Find in Page" and "Quick Switch" features, makes all users Premium by default, and so much more! Ferdi supports multiple accounts on any service, has full proxy support and is also cross-platform. If you're looking for a much better experience from Franz or just want a more efficient way of using your apps and services, Ferdi is definitely the way to go. Ferdi is compatible with Franz so you can easily switch your existing Franz account if you have one.

Professional and powerful brainstorming and mind mapping software tool,open source,Eclipse Community Award 2008 winner,often used for capture ideas,knowledge/project management and GTD,supporting fishbones/org-charts/tree charts/spreadsheets,easy-to-use.

qOrganizer is a general organizer that includes a calendar with schedule,reminders,journal/notes for every day, to-do list.But provides features useful for students such as:timetable and a booklet for marks and absences.It's designed to be easy to use.

Makagiga is an open-source, easy-to-use, portable application for doing a variety of tasks, such as todo listing, text editing, or RSS reading. Plugins are used to implement its various capabilities.

Standard Notes is a free and open source private notes app that features unmatched simplicity, end-to-end encryption and powerful extensions. You can compose any kind of note easily, and trust that you’re writing in total privacy.

RedNotebook is a graphical diary and journal helping you to keep track of notes and thoughts. It includes a calendar navigation, customizable templates for each day, export functionality and word clouds. You can also format, tag and search your entri

Osmo is a handy personal organizer, which includes calendar, tasks manager, address book and notes modules. It was designed to be a small, easy to use and good looking PIM tool to help to manage personal information.

SO Planning is a Simple Online Planning tool. Allows you to plan working periods for each person of your team, in a visual / printable result. Shows a line by person and the corresponding working days. See http://www.soplanning.org for details.

GloboNote is a free and easy to use desktop note taking application. It lets you create sticky notes, to-do lists, journals, reminders and other notes in one place. There are no limits to the number of sticky notes you can create. Notes can be organize by groups and search using the search tool. GloboNote can be run in any OS that has Java 8 installed.

Tabbed notebook with RichText editor, multi-level notes and strong encryption. Added new features to Marek's KeyNote: checkboxes on children of selected nodes, hidden nodes, alarms on nodes.

Rachota is a portable application for time-tracking your work on different projects. It runs on Windows, Linux, Solaris and Mac. Rachota displays time data in diagram form, creates customized reports or invoices and provides suggestions to increase your efficiency.

Omni-Notes is a powerful open-source note-taking application for Android designed to be both smart and simple. It has a clean and simple Material Design interface and is packed with plenty of smart features. These include image, audio and generic file attachment, a To-do list, Google Now integration, numerous widgets and so much more. Omni-Notes takes note-taking to a whole new level, making it more convenient and integrated. It's an ideal note-taking application particularly for old Android phones without such apps, giving users an updated look and experience when taking down notes.

pin 'em up is a tool for placing small notes/post-its (e.g. TODOs/Reminders) on your desktop and organize them in various ways (categorize,hide,upload,export,...). Due to platform independence, the notes can also be shared on different operating systems

JTrac is a generic issue-tracking web-application that can be easily customized by adding custom fields and drop-downs. Features include customizable workflow, field level permissions, e-mail integration, file attachments and a detailed history view. While the last release happened a long time ago, work has resumed in 2021 to bring JTrac back to life. If you find bugs, have patches or questions, open a ticket and get the ball rolling. See https://sourceforge.net/p/j-trac/wiki/NewFeaturesTrunk/ for what's new, and grab a war file of the beta version if you want to give it a try at https://sourceforge.net/projects/j-trac/files/jtrac/2.2.0-b2/

Personal wiki that lives in one self-modifying XHTML containing software, interface and data. Very useful for creating small websites and mantaining notes or todo-lists; completely javascript-programmable, supports encryption and file embedding.

SciPlore MindMapping is based on FreeMind but extended with features for students & researchers. It integrates mind maps with reference and pdf management (BibTeX support & PDF Bookmark import). Keywords: Mind maps, Mind Mapping, MindMap, JabRef

sleek is an open-source todo app that makes use of the todo.txt format. sleeks GUI is modern and simple but still offers a decent set of functions which help users getting things done. sleek is available as a client for Windows, MacOS and Linux. Users can add contexts, projects, priorities, due dates or recurrences to their todos. These todo.txt attributes can then be used in full-text search, as filters or to group and sort the todo list. sleek manages and watches multiple todo.txt files continuously for changes, which makes it easy to integrate sleek with other todo.txt apps. Also users can switch to dark mode and choose from multiple languages. Todos with due date or repeating todos will trigger notifications and completed todos can be hidden or archived into separate done.txt files. If users have tons of todos, a compact view can come in handy.

Piggydb is a flexible and scalable knowledge building platform that supports a heuristic or bottom-up approach to discover new concepts or ideas based on your input. You can begin with using it as a flexible outliner, diary or notebook, and as your database grows, Piggydb helps you to shape or elaborate your own knowledge. Piggydb is a Web application provided as a self-contained package that contains a Web server and database engine. With Piggydb, you can create highly structured content by connecting knowledge fragments to each other to build a network structure, which is more flexible and expressive than a tree structure. Fragments can also be classified using hierarchical tags.