
Fresh apple means the whole fruit: juiced, muddled or cut into the drink. Which apple matters more than you would think. A Granny Smith is sharp and low in sugar; a Gala or a Fuji is sweet and mild; the same recipe made with one and then the other gives two measurably different drinks.
Juice and slices share nothing but the fruit. Fresh juice is sharp and browns within the hour; anything from a carton is sweeter, flatter and stable, so the acidity has to come back from somewhere.
Bottled apple juice
Pasteurized and usually sweeter, with the fresh aromatic edge gone. Fine as bulk liquid, wrong wherever the apple is the point.
Cider
Fermented, dry or sweet, alcoholic and often sparkling. It is a different ingredient rather than a stand-in for the fruit — it brings strength and fizz where the apple brought flesh and acidity.
Whole apples keep for weeks in the fridge and go mealy at room temperature. A cut apple browns within minutes, and fresh juice separates and browns almost as fast, so it is pressed to order.