Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Plan - Plan is a better way to organize.
Outplanr - Turn your to-do list into a real work plan
Tasks - The new task app from the team that brought us Wunderlist, Microsoft To-Do is a great way to manage tasks. List everything you need to do—or import tasks from Outlook, Todoist, and Wunderlist so you don't have to start over.
Clean Google Calendar - Makes Google Calendar look nicer & launches as a desktop app
ProductiveApp.io - Productive is a habit tracking application.