I have used both Trello and Asana at various times over the past 3 years. Your article is an excellent breakout of each applications features. I think that of the usefullness of either app relates to “when” it is being used. Your suggestion to use Trello for visual thinking and Asana for checklist follow-up and management strike me as compelling. But it also begs the user interface question of why not both is a single app? I’m thinking back to the flexibility of GrandView in the DOS days of the late 1980's. And then moving forward to concept mapping with Mind Manager applications (FreePlane and others as well).