3D Cohort Retention Skyline & Funnel Tunnel

This simulator renders mobile-analytics event data as two connected 3D structures. A stream of instanced spheres flies down a funnel tunnel, crossing three gate rings — install→signup, signup→first action, first action→purchase — with each gate rolling its own conversion rate live, so drop-off is visible as spheres veering off and reddening rather than a static bar chart. Every user who clears all three gates is credited to the current signup-week cohort, and once a cohort closes it becomes a new column in a rotating retention skyline: a grid of instanced bars whose heights are recomputed every frame from a stretched-exponential retention curve, showing at a glance how each cohort's engagement settles over its first 60 days.