You can subscribe to tasks and have an email sent to you every time something changes on a task. Now it's even better because you can subscribe other people to tasks. It's a handy way to keep everyone in the loop without having to get too many emails.
The subscribe link is still on the right side of the task action menu, but now it allows you to select multiple users:
Click on "Subscribe" and select the users you wish to add to the task. If you’re getting notifications for a task that you’re not interested in, you can unsubscribe from the task.
You can see a small eye icon on the tasks that you have subscribed to.
To quickly subscribe yourself to a task use the keyboard shortcut. Hover your mouse over the task and press the "s" key.
Another way to get users attention is to @mention them using their name. Here's a short guide how to use it https://www.breeze.pm/blog/51-get-your-team-members-attention-by-mentioning-them