Taskade - Make lists, organize your thoughts, and be inspired to get things done. Taskade is a collaborative space for your tasks.

Microsoft To-Do - Task management tool

Todoist - Todoist is a to-do list that helps you get organized, at work and in life.

The ToDon't List - A to-do list for avoiding the things you shouldn't be doing

doo - A smart, simple app for reminders and to-dos

tray - simple site builder for sharing notes and links