Habitica is a habit and task manager that gamifies productivity by turning your to-do list into a role-playing game — completing real tasks earns experience points, gold, and gear for your avatar, while missing tasks damages your health. Founded in 2013 through a Kickstarter campaign, Habitica built a passionate community of users who found traditional task apps too dry to maintain consistent engagement. Its social party system lets friends hold each other accountable by sharing a health bar that suffers when anyone in the group misses tasks.

Reference:

Habitica on Wikipedia

https://en.wikipedia.org/wiki/Habitica