You can add new tasks simply by typing the name in the input box.
You can also instantly tag, assign to user or list the new task. Just type the corresponding character (@, !, #) with a text, a small drop down box appears and you can select the desired value.
The users and lists must exists before you can assign the task to them, tags on the other hand can be created automatically - start typing and you have an option in the drop down list to create a new tag.
If you don't want to tag, assign to user or list then type your description and don't select anything from the drop down list.
You can also estimate tasks by ending it with time value. Ex. "Do something creative 1h30m" . Then the 1h30m is added to the task as a time estimate.