Way of Life - Habit tracking on iOS
Streaks - The to-do list that helps you form good habits.
Taskful - Deadlines, meet your match.
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.
ToDoList - Windows desktop application to stay on top of your daily tasks.