I think Trello works great for very focused teams. For example, let’s say just a small UX team of 5 or 6 managing their tasks. I create tasks to be completed for a week, maintain my to-dos, and prioritize. Works great as long as it is a small group of people who collaborate and work closely with each other. At work, for managing tasks for bigger teams — say a team of engineers, PMs and designers, we use JIRA. For smaller teams, we use Trello. Also, Trello is great for individual task management as I mentioned.