Habitica

Habitica treats your routine as a game. You add habits you want to repeat, daily tasks you want to keep and one-off to-dos, and each one you complete earns your character experience and gold. Missing a daily costs health, so letting things slide has a visible cost on screen.

People who like games often stick with it longer than a plain checklist, and the party feature lets friends join the same quests, so skipping a daily affects the group as well. It runs on the web and on phones, and the core app is free, with an optional subscription for extra items.

It suits people who need a reason to come back each day. If you want a quiet, minimal tracker, the game layer may feel like noise. The code is open source, which some users like for transparency about how the app works.