Trello

From Fog Creek Software:

Trello is a collaboration tool that organizes your projects into boards. In one glance, Trello tells you what's being worked on, who's working on what, and where something is in a process.

With a simple board and card system, any project, task list, or process can be visually represented and easily managed. No more cumbersome software for you just the speedy and simple elegance of Trello to organize everything.View your Trello boards, lists, cards and notifications with the Trello app for iOS and keep up to date with the activity of your team members.

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