Astrid is described as 'At its core, Astrid is a open source todo list that helps you get stuff done. That's why Astrid makes it really easy to create lists of tasks, as well as set priority, set due dates, and times' and is a popular todo list manager in the office & productivity category. There are more than 100 alternatives to Astrid for a variety of platforms, including Windows, Web-based, Android, iPhone and Mac apps. The best Astrid alternative is Todoist, which is free. Other great apps like Astrid are Tasks.org, TickTick, Workflowy and Habitica.
Due Today offers a powerful solution to organize your tasks and projects using a mixture of David Allen's Getting Things Done methodology and your own organizational scheme.
Yodiz is the leading Agile Scrum tool and issue tracker. With it's innovative UI, simple UX and great set of features, it's probably the best tool.
Web-based Project management and task planning for people who hate project management and task planning. For individuals, teams and small businesses.
MyAsana is a native Android app and widget for Asana (www.asana.com). Asana is a task list and project management web application for individuals and teams. It is great for organizing daily tasks and sharing them within a project team or family.
Taskline, task management software for Microsoft Outlook, automatically schedules tasks to puts you in control of your task list.
TaskJot - GTD app made for Blackberry featuring sync to Toodledo.com. A Blackberry todo application more convienient than any other!
Wieldy is a free to-do list manager that is based on the principles of GTD (Getting Things Done). It allows you to manage your to-dos in a simple but effective way. To-dos can be created as thoughts and actions, which can then be assigned to the Next Action, Today, or Someday...
Remember The Task is a light-weight ToDo application that allows you to maintain a list of tasks to be done. It Syncs with Remember The Milk so you can manage your tasks on the go using RTM.
Task List Guru is a freeware to-do list manager that stands out from the crowd thanks to two things:
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