Lunatask - All-in-one encrypted to-do list, habit and mood tracker, journaling and notes app
Microsoft To-Do - Task management tool
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Things - Things is an easy to use task manager.
doo - A smart, simple app for reminders and to-dos
Asana - Asana project management is an effort to re-imagine how we work together, through modern productivity software. Fast and versatile, Asana helps individuals and groups get more done.