An apple that has just fallen from the tree looks finished. But inside it keeps living: it breathes, its starch turns into sugar, and its acid fades — day by day, while it sits on the kitchen counter.
Guess first: does the apple get sweeter or more sour as it sits in the bowl?
Day 21: less acid, more sugar — and softer flesh.
Drag across the picture to scrub through the days, or tap for the next day.
The bars show the direction of change, not exact measurements.