Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Nirow - Habit tracking: Automated, Siri-ed, Calendar-ed, and More!
doo - A smart, simple app for reminders and to-dos
Gone - An ephemeral to-do list
Simplenote - The simplest way to keep notes. Light, clean, and free. Simplenote is now available for iOS, Android, Mac, and the web.
Taskful - Deadlines, meet your match.