How do I see how much time my colleagues have spent on the task?

Click on any card on any dashboard and you will see the Timing section in the right panel. There you can see the report showing how much time your collaborators have spent working on the task.

If you don’t have Time Tracker, you will not be able to see the Timing section of the right panel. However, as far as each time entry appears as a simple comment in the Comments section of the right panel – you still will be able to see the time spent by your collaborators.