Gone - An ephemeral to-do list
Habit List - Create good habits and break bad ones with the app that keeps you focused.
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Momentum - Agile goal and performance management
Check - Check is a unit testing framework for C, which runs on environments such as GNU/Linux, GNU/Hurd, BSD, and Mac OSX.
Streaks - The to-do list that helps you form good habits.