Never worry about forgetting things again.

An interactive terminal based todo.txt file editor with an interface similar to mutt.

A comand line interface to manage hierarchical todos. Each task has a title, a long text description, a deadline (tudu warns you when the date is close), and a scheduled date. There are categories and priorities.

A minimal clone of Wunderlist, with 30% of its features. GTD oriented. It stores the task list in a hidden JSON file in the home directory, making it easy to backup or share them.

Minimalistic todo manager that uses a simple plain text file to keep track of items; implemented as a shell script.

Todo manager with advanced features; dedicated synchronization server available; many plugins and related tools; healthy software project.

A fully-featured task manager encapsulated within a Python script (just carry around the script to retain all the TODOs). When the script is run, a Python shell is opened, where task-related commands can be entered (ADD, LIST, etc.); a pity that commands are uppercase, which requires the annoying use of the Shift key.

Tasky is a command-line interface to Google's Tasks API.

It is meant to parallel the functionality of Todo.txt.

Taskbook is a simple, free, open-source, command line-based utility app for creating and managing notes and tasks across multiple boards.

It uses a minimal syntax and being security conscious, automatically saves all your data to the storage to avoid corruption or sharing with unpermitted parties. By default, the data is stored in JSON file at ~/.taskbook/storage.

etm provides a simple, intuitive format for using plain text files to store data, a command line interface for viewing events and tasks in a variety of convenient ways and a cross-platform, wx(python)-based GUI for creating and modifying events and tasks as well as viewing them. Displayed items can be grouped by year, month, day, week number, quarter, context, keyword, location, user, file and/or priority and can be filtered in comparable ways. The display shows the number of items and time totals broken down by group headings. A display of busy and free times is also supported. Alarms are supported for events and repetition for both events and tasks in a powerful and flexible manner.

todo.txt-cli - A simple and extensible shell script for managing your todo.txt file.

QTodoTxt - Cross Platform todo.txt GUI