Restyaboard

Restyaboard is an open-source, self-hosted alternative to Trello and Asana. It provides Kanban boards, tasks, checklists, and labels.

Being open-source, it offers full control and customization for agencies with technical teams who want to host their project management data on their own servers for security or compliance reasons. It can be extended and integrated via its API. The software itself is free, though hosting and maintenance costs apply. It ranks as a decent choice for privacy-focused or cost-sensitive agencies with the technical capability to deploy and maintain their own instance of a visual PM tool.