
Apple brandy is a fruit brandy distilled from fermented apple juice or cider, unaged or oak-aged.
Apple and oak are the two halves, and bottles nearby carry them in different proportions — some are apple spirit cut with neutral, some are years in a cask. Read the label for how much of each you are getting, because the word on the front does not settle it.
Both are made from apples, but calvados must be oak-aged and comes out deeper and softer, where apple brandy can also be young and unaged, sharper and fruitier. In a stirred drink the young one reads greener and needs a shorter stir.
Apple liqueur
Apple liqueur is flavoring and sugar on a neutral base; apple brandy is distilled from the fermented cider itself. The liqueur is sweeter and weaker, so it cannot hold the spirit line of a drink on its own.
"Any apple brandy is calvados"
No — calvados is protected by origin (AOC) and made only in Normandy. Apple brandy from the United States or anywhere else is not calvados, however it is aged.
Cider at around 5–8% is distilled and then either bottled young or aged in oak: that is what decides whether the brandy stays clear and sharp or darkens and softens.