Comment by gerdesj

Bloody 'eck. This sounds like a chat around the back of the bike sheds off of the '70's onwards.

Yes, apple pips do have a tiny amount of cyanide in them (but why)

This is a from a reasonable source and relates to cherries: https://www.bbc.co.uk/news/uk-england-lancashire-40738573

I think we can assume that apples and cherries are OK to eat. Apple pips are fine and why on earth would you want to crunch through a cherry stone.