Habitica - Habitica is a free habit building and productivity application.
Everyday - Take a photo of yourself everyday.
Loop Habit Tracker - Loop Habit Tracker (AKA uhabits) helps to create and maintain good habits in order to achieve their...
My Effectiveness - AndTek
Coach.me - Coach.me is a coach that goes everywhere with you, helping you achieve any goal, change any habit, or build any expertise.
Beeminder - Beeminder