iOS: Jerry Seinfeld's productivity secret—also known as don't break the chain—crossing off a day on a calendar when you complete a task. Each X'd day creates a chain, and you'll quickly find that you'll keep doing your work to avoid breaking it. I've been using this method for over six months now and it's great, but six months of calendars for four separate tasks takes up a lot of space. An app like Wonderful Day takes up a lot less. More »