TeamWork.com vs Habitica

Tasks are grouped in task lists and can have subtasks. Each task list can be assigned to a particular set of users, aligned with a milestone and have notes. Each task in the task list can have a description, a start and a due date, attachments, priority, manually set progress, followers, dependencies, be assigned to a particular set of users and set to repeat. Each subtask has the same configurable properties except instead of the ability to assign people, subtasks can be commented on.

It's possible to limit projects only to the necessary features so that unnecessary functionality doesn't get in the way and clutter up the interface.

Gantt charts, calendar and an easy overview of huge amount tasks.

The app allows creating a party with other people and go on a quest together. Here, your actions affect not just you, but everyone else in the party as well. If you fail a task, the party loses health, if you complete a task, the party gains experience, etc.

The app takes cues from role playing games by having a system that rewards certain behavior with experience points, levels, and gear upgrades. It also allows you to set custom rewards that you come up with yourself such as watching an episode of your favorite TV show.