Trello is the kanban board everyone already understands: cards, lists, drag and drop, due dates, checklists. Power-Ups and Butler automation stretch it further than people expect, and the free plan covers a lot of personal and small-team use.
It suits solo founders and small teams who need a visual board, not a work platform. Once dependencies, reporting or cross-project views matter, teams usually graduate to Asana or ClickUp.