I've used Polar Habits for a few weeks. I love the idea behind it, that if you mess up your habit for one day it's not the end of the world. Habit forming should not be a binary thing, win or lose. It's the overall progress that counts and that's why I like what Polar Habits is building. The overall aesthetic is very pleasing too, which is important as it makes me want to come back to use the product each day.