Notetaking, Outliner, PIM, Calendar, To-Do list apps

Simple way to manage your todo list in AJAX style.
Written in PHP and jQuery.
Data stored in SQLite or MySQL database.
Distributed under the GNU GPL License.

Features

Multiple lists
Task notes
Tags (and tag cloud)
Due dates (input format: y-m-d, m/d/y, d.m.y, m/d, d.m)
Priority (-1, 0, +1, +2)
Different sortings including sort by drag-and-drop
Search
Password protection
Smart syntax improves creation of tasks (usage: /priority/ Task /tags/)
Print-friendly CSS
Style for mobiles devices

Stacks is an easy to use task manager that helps to organize your tasks in an elegant and intuitive way. Using kanban paradigm for managing your projects Stacks offers a flexible and visual way to organize your tasks with ease. Combining powerful features like tags, task grouping, quick search and attachments with a beautiful user interface, Stacks aims to make task management both easy and fun.

Features:

• Colored tagging system
• Quick task search
• Task attachment
• Mark task as complete or to do
• Sync through iCloud Drive, Dropbox or any other file syncing service
• Attachment preview
• Write your tasks in Markdown
• Add address or coordinates and preview the map with zoom
• Add a link
• Automatic backup of your library
• Drag and Drop
• Task due date
• Create reminder and calendar event from task
• Beautiful image preview

Lifeograph is an off-line and private journal and note taking application.

A hierarchical note taking application, featuring rich text and syntax highlighting, storing data in a single xml or sqlite file.

An open source note taking and to-do application with synchronisation capabilities.

Original Feature List (with personal marked Highlights)

>> Notes can be arranged into arbitrarily deep tree. Single note can be placed into multiple places in the tree (see cloning)

• Rich WYSIWYG note editing including e.g. tables, images and math with markdown autoformat
• Support for editing notes with source code, including syntax highlighting
• Fast and easy navigation between notes, full text search and note hosting
  >> Seamless note versioning
  >> Note attributes can be used for note organization, querying and advanced scripting
  >> Synchronization with self-hosted sync server
• Strong note encryption with per-note granularity
  >> Relation maps and link maps for visualizing notes and their relations
  >> Scripting - see Advanced showcases
• Scales well in both usability and performance upwards of 100 000 notes
• Touch optimized mobile frontend for smartphones and tablets
• Night theme
• Evernote and Markdown import & export
• Web Clipper for easy saving of web content

Powerful knowledge base that works on top of a local folder of plain text Markdown files.

KeyNote NF is a flexible, multi-featured tabbed notebook, based on Windows standard RichEdit control. It's always accessible with a single keypress, even if you work in another application.

The basic idea in KeyNote NF is that you can include many separate notes within a single file. This means that you do not need to open several files - for most purposes it is enough to create only one file and hold all your notes inside it. With the addition of the tree-type notes, you now have a three-dimensional notebook: many notes within one file and a multi-level, nested pages within a single note. Keynotes interface and behavior are extremely configurable.
KeyNote is the only information manager that offers a combination of simple and tree-type notes, rich text editor, ability to mix freely many notes of different types in a single file and secure encryption. This makes KeyNote the most flexible and one of the most powerful applications of this kind currently available. Some functions, such as "virtual nodes", per-file configuration settings, multiple backups or WordWeb integration are unique and, to my knowledge, not supported by any other notebook program, freeware or shareware.

With powerful text formatting capabilities, easily navigable interface and additional features such as styles, macros, plugins, and templates, KeyNote is has become the favorite note keeper, diary, outliner, knowledge base and information manager for thousands of users.

MemPad is a plain text outliner and note taking program with a tree structured index.
All pages are stored in a single file.
User interface available in 20 languages.

AlephNote is a lightweight note taking desktop app usable with multiple backends:

Standard Note
With the StandardNotePlugin your notes get synced with a Standard File server. Your notes are locally encrypted and cannot be read from anyone but you.

Simplenote
With the SimpleNotePlugin you can sync your notes with the free SimpleNote online service

Nextcloud/owncloud notes
The NextcloudPlugin syncs your notes with the notes app running on you own private nextcloud/owncloud instance

Local
You can also simply not use a remote backend and either use the HeadlessPlugin (don't sync the notes anywhere) or the FilesystemPlugin (sync the notes with another folder).™

Notable is a cross-platform note app. Notes are plain Markdown files, their metadata is stored as Markdown front matter. Attachments are also plain files, if you attach a picture.jpg to a note everything about it will be preserved, and it will remain accessible like any other file.

FEATURES

• No proprietary formats: Notable is just a pretty front-end for a structured folder and uses plain Markdown
• Notes get rendered as GitHub-flavored Markdown
• Indefinitely nestable tags
• Fuzzy search
• Code syntax highlighting
• Multi-note editing and search/replace

CryptPad is a collaborative office suite that is end-to-end encrypted and open-source.

Etherpad is a highly customizable Open Source online editor providing collaborative editing in really real-time.

Collaborating in really real-time
No more sending your stuff back and forth via email, just set up a pad, share the link and start collaborating!

Etherpad allows you to edit documents collaboratively in real-time, much like a live multi-player editor that runs in your browser. Write articles, press releases, to-do lists, etc. together with your friends, fellow students or colleagues, all working on the same document at the same time.

All instances provide access to all data through a well-documented API and supports import/export to many major data exchange formats. And if the built-in feature set isn't enough for you, there's tons of plugins that allow you to customize your instance to suit your needs.

You don't need to set up a server and install Etherpad in order to use it. Just pick one of publicly available instances that friendly people from everywhere around the world have set up. Alternatively, you can set up your own instance by following our installation guide

This opensource project is based on the original Etherpad (by Appjet) , made from AppJet Inc. , later acquired by Google which open-sourced the key libraries required to create Etherpad Lite.

TiddlyWiki is a highly customizable notewiki for capturing, organising and sharing complex information.

TiddlyDesktop is a special purpose web browser for working with locally stored TiddlyWikis.

ToDoList is software in the category of Task Management, Project Management, Productivity, “Getting Things Done” (GTD), Scheduling, and Collaboration.

Track your tasks and projects in a plain text file, todo.txt. A todo.txt is software and operating system agnostic; it's searchable, portable, lightweight and easily manipulated.

todotxt.net : A minimalist, keyboard-driven Windows GUI for your Todo.txt file

Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud.

Full-featured Information manager, inspired by award-winning Ecco Pro. Outliner with user-defined columns, Calendar, Gantt and Timeline charts, Rich-text pane, MindMap, Pivot tables and charts.

Noteliner is an outlining tool for keeping track of todos and other information about projects. Noteliner lets you create a hierarchy of notes to track and structure your work. You can also give these notes due dates, indicate which ones need attention, assign people, prioritize, or mark them complete. Different views allow you to see all the notes assigned to a particular person, those that are over due, need attention or are dated.

This program helps you organizing your dates and tasks and reminds you of upcoming events.

BORG is a combination calendar and task tracking system. The calendar supports all sorts of appointments and also a simple todo list. The calendar functionality is similar to that of other PIMs, such as Microsoft Outlook, Mozilla Calendar, Palm Desktop, Yahoo Calendar, etc... The Task Tracker goes way beyond todo's and might better be called a project tracking system.

BORG is basically meant to be a small self-contained Java application that you can run locally (i.e. without a network). Many users run it from a thumb drive.

Features

Nice Month-at-a-time view
Week and Day Views
To-Do list
Month-print
Repeating Appointments
Private Appointments that do not show by default (for recording things like "rectal exam 2pm" that you don't need your friends/coworkers to see over your shoulder).
Pop-up reminders
Email reminders
A Task/Project Tracking System
A simple address book
MySQL DB, HSQLDB, generic JDBC
XML import/export
more ...

Keep a nice, transparent calender on the desktop. Double-click on a day to enter a description.

The Calendar app is a user interface for Nextcloud's CalDAV server. Easily sync events from various devices with your Nextcloud and edit them online.

TreeLine just stores almost any kind of information. A tree structure makes it easy to keep things organized. And each node in the tree can contain several fields, forming a mini-database. The output format for each node can be defined, and the output can be shown on the screen, printed, or exported to html. TreeLine can also act as a basic editor for any kind of XML file.

Symphytum is a personal database software for everyone who desires to manage and organize data in an easy and intuitive way, without having to study complex database languages and software user interfaces.

With Free Address Book - Free Phone Book you can note the addresses, phone numbers, mobile, fax, company name, country, city, website address and email addresses of your contacts and partners.

Add your custom fields, where you can store your special data, which is not default in this program.

You can easy customize printable list of contacts and details page of selected contact.

Export/import your contacts in CSV format.

Phone Book is absolutely free!

Organize your contacts easy and fast!

Open Contacts is an advanced address book program for managing contact info of individuals and organizations with relationships. Distributed as freeware, the program was designed for people who need more beyond ordinary address book programs in order to improve dynamic interactions with contacts. In addition, with SyncML for Open Contacts, you may synchronize contact info with smart phone, PDA and Web address books etc.

The Nextcloud contacts app is a user interface for Nextcloud's CardDAV server.

A safe home for all your data – Access & share your files, calendars, contacts, mail & more from any device, on your terms.