I want to be able to put tasks on multiple lists at once and have them connected so that if I check the task off on one list it will automatically get checked off on any other list, as well. If it’s not possible to do this, then being able to sort by tags is a good workaround (e.g. sort all tasks from all lists according to a tag so that I can go through the tagged tasks and complete tasks that are currently on different lists at the same time).