Well there is but I don't know if I'd trust it, frankly. Periodic Calendar. Open source and licensed under the GPLv3. Thing is I don't think it's maintained anymore; the most recent version was released 7 years ago, and the most recent copyright date I've found was from 2013. Source: about 2 years ago

Habitica is one of the coolest web apps (they also have iOS and Android apps) I’ve seen in a while - it helps you organize your life, tasks, and habits through the RPG game! Imagine a Kanban board like Trello, but for each task you complete, you earn XP and gold, and you can even team up with friends to take up quests. - Source: dev.to / 5 months ago

Habitica, an innovative daily planning app, takes a unique approach to task management by transforming your daily routine into an exciting role-playing game (RPG). Combining the principles of gamification and productivity, Habitica offers a refreshing and engaging way to stay organized, motivated, and on track with your goals. With its intuitive interface and vibrant visuals, this app turns mundane tasks and... - Source: dev.to / 11 months ago

Habitica: this app turns your life into a role-playing game, with your tasks and habits to complete/achieve. Source: 11 months ago

Works with Habitica (https://habitica.com/), an app that turns habits into RPG games! When reviewing with Anki, you can earn experience and items. (Habitica is also free). Source: 11 months ago

> From these experiences, I’ve realized that avoiding bad habits is just as important as cultivating good habits. Avoidance rarely works I think. I'd say replacing negative habits with positive ones is a better long term strategy. Can recommend the App Habitica for this, free and open source. There are Android and iOS clients for it. Makes habits dailies and todos more fun. Not affiliated, only fixed an... - Source: Hacker News / 11 months ago