Gone - An ephemeral to-do list
Timing - Timing is the best way to keep track of the time you spend with your Mac.
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
RescueTime - Time management software that shows you how you spend your time & provides tools to help you be more productive.
Microsoft To-Do - Task management tool
Memory by Timely - An intelligent timeline of everything you did in a day.