We strongly believe most of the things we do daily do not have a due date... That's why we offer the Now, Plan later and Someday categories to define when you'd like to wok on a task vs. when it may be due.
That being said, when it come to working with due dates it's clearly more convenient to display them as a calendar.
From a Subject's page, you can create a task using the + button within a date. It automatically sets a due date to the day you created it in. Need to change the due date? Simply drag & drop the task into another date. The due date will change accordingly to the date you drop the task into.
Would you rather organize your work week by week? We also added a weekly view, which shows tasks with due dates for a given week, broken down per subject member. On this view you can also drag & drop tasks to change the due date, but also to change the assignee.