What are some alternatives?
WorkFlowy - WorkFlowy is an organizational tool that makes life easier. It's a surprisingly powerful way to take notes, make lists, collaborate, brainstorm, plan and generally organize your brain.
Checkvist - Checkvist is a tool to create and share checklists, plans, and outlines.
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
Moo.do - Moo.do Application
OneNote - Get the OneNote app for free on your tablet, phone, and computer, so you can capture your ideas and to-do lists in one place wherever you are. Or try OneNote with Office for free.
Orgzly - Outliner for notes, tasks and to-dos