Firepoker - Agile Planning Poker powered by Firebase and AngularJS
Planning Poker - Open source implementation of planning poker game (collaborative online estimation/voting tool).
Scrumpoker Online - Scrumpoker is an online and free-to-use poker planning tool where teams can do estimation about their projects.
Taiga - Project management platform for agile developers & designers
Methodist.io - Methodist provides free online agile services for distributed agile teams. Planning poker & Retrospective online boards.
Craft.io - All-in-one product management software for entire product lifecycle