Habitica - Habitica is a free habit building and productivity application.
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Coach.me - Coach.me is a coach that goes everywhere with you, helping you achieve any goal, change any habit, or build any expertise.
Any.DO - The #1 task management app used by over 11 million people globally, Any.do is your free mobile and online task manager for Android, iPhone, Web and more.
Loop Habit Tracker - Loop Habit Tracker (AKA uhabits) helps to create and maintain good habits in order to achieve their...
Microsoft To-Do - Task management tool