Before the Sweet Apple Acres update, the Zap Apple Stand was mentioned in english.loc, in the completion message STR_BUILDING_FINISHED_ZAPAPPLE ("Your Zap Apple Stand is complete!"). This mention was present from the first released version of the game.
Slot Level Requirement
The Zap Apple Stand during Hearth's Warming Eve.
The Zap Apple Stand during the Tree of Harmony Event.