Past Due Date
You don't allow a due date prior to the date of today? Sometimes, I want to add a task with a gone date to flag it as overdue or see it at the top of a list. Most other task management apps allow this. To be fair, it's particularly uncomfortable at the moment as I'm moving all my tasks (and that of my team) to ToDoist from another app and some of the tasks are overdue but I can't put in the original deadline date.