By clicking on it, you'll receive alerts whenever you get a new notification - as long as your browser is open.
Here's when you will receive notifications:
§ when a team member comments on a task you are tagged in, mentions you in a comment with your @username or when someone comments on a task you have previously commented on
§ when a task is assigned or unassigned to you
§ when a task you are tagged in is changed
§ 30 minutes before a task is due
§ when a team member changes the name or number of rows or the sprints in a project that is shared with you
§ when a task you are tagged in is completed or uncompleted
§ when a project is shared or unshared with you
§ the occasional news announcement from Sandglaz
You can also receive alerts when tasks are due by setting up an iCal feed.