Todoist
Karma points and levels turn consistent task completion into visible progress.
Todoist is a multi-purpose task and to-do management app whose gamification layer is Karma: a running score that grows as you complete tasks on time and use the product well, with levels that rise as positive Karma accumulates.
Karma is quiet by design. It does not block anything or demand attention; it just makes consistency visible, which is enough to give long-term users a sense of momentum.
The design lesson: a lightweight score can reward good product behavior (labels, recurring deadlines, on-time completion) without turning a utility into a game. Calibrate the volume of the mechanic to the seriousness of the tool.
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