You can use codes to add bold, italics or to insert links. For example:

Bold text

What you enter How your text appears
!!Bold text!! Bold text
__Italic text__ Italic text
http://google.com/ (Google) Google

Quick priority assignment

In an item's text field, if you enter !p3, Todoist will assign priority 3 to the item. Once you save the task, !p3 will be deleted from the text, and the item will be listed as priority 3. Any priority level can be assigned with this shortcut, such as !!1 for priority 1, !p2 for priority 2, or !p4 for priority 4. For example:

Priority 1 task