Trello is a web-based, kanban-style, list-making application and is developed by Trello Enterprise, a subsidiary of Atlassian. 🔑 Created in 2011 by Fog Creek Software, it was spun out to form the basis of a separate company in 🔑 New York City in 2014 and sold to Atlassian in January 2024.

On the surface, Planner and Trello are quite similar. Both are online Kanban tools 🔑 designed to streamline task and project management. Both belong to extensive product suites of Microsoft and Atlassian respectively.