cnvs.app is a free online whiteboard and kanban board that opens from a link, with no signup for anyone and a public MCP endpoint for AI agents. These pages compare it with the tools people usually search for. The comparison pages cite the vendor's own pricing or documentation pages and state when the facts were checked, because plans and limits change.
Plans and limits change, so check the vendor's own page before you decide; each comparison names the pages it was written from and the date they were checked. One limit applies to every cnvs.app board: a board that nobody opens for 30 days is deleted, so save a .json backup of anything you need to keep.