Power User Curve

The power-user curve is a histogram grouping users by their number of active days in a window (say 28 days), to show the share from casual to daily users.

The power-user curve (sometimes the smile curve) is the visual form of the L28 distribution and was built to correct a misleading picture: the average of engagement. When you stack users by active days, healthy sticky products usually show a bump on the right — a mass of users who come nearly every day — and it is that right-side bump that produces durable engagement, not the middle mass. The curve's value is in its trend: if the right bump grows month over month, the product is turning casual users into a habit; if it shrinks, the base is eroding even amid new-user growth. The common trap is watching a single number (average active days) instead of the whole shape; that number can hold steady while the shape — and the real health — has completely changed. This curve complements the retention chart, not replaces it: retention says whether a user returns, the power curve says how deeply.