Fuck that. Tipping culture is ridiculous as it is. No way in hell someone deserves a tip showing you the capabilities of an iphone. Especially not with the current POS systems that ask for a minimum of 20%.
Yeah isn't it literally your basic minimum job requirement to be showing people the capabilities of an iphone? You want me to buy your product, YOU show me why I should want it.
or you? the potential customer paying with a tip to the store's employee??