A flapping is an apple with imprint
The flapping is supplied by the company behind send an apple. With light rays they engrave the apples with one of the standard images including self-delivered text. It is also possible to deliver your own design, but this has a longer delivery time. The apples are bought at the auction, so that the delivered flapples can be kept for as long as (or perhaps even longer) than the apples bought in the supermarket.