GitKraken Timelines - Communicate major project milestones and deadlines for free
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
GitKraken - The intuitive, fast, and beautiful cross-platform Git client.
Instagantt - Instagantt is a powerful and intuitive Gantt chart tool to enable teams to plan, manage and visualize their projects easily. Manage your schedules, tasks, timelines, and workload like a Pro. Try it for free.
Kanbanier - Clean iOS and Mac kanban/trello with flexible views
Chronologies.io - Your Memories, Your Story, Your Timeline