Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
iBucket - A social bucket list apps that helps you achieve your goals & trips. Available for iOS, Android and Web. Dream it. Plan it. Do it.
TaskPaper - Plain text to-do lists for Mac
Kurator - The premier Chrome extension for savvy researchers and publishers alike. Curate your interest and publish to your website, newsletter and social media sites directly from the browser.
Microsoft To-Do - Task management tool
FocusOKR - Focus and achieve your goals using Objectives and Key Results