Many (but not all) dietary vegans are also holistic vegans, meaning they choose cleaning products, clothing, beauty products without animal ingredients and aren't tested on animals.
Same thing as 'vegan' imitation leather products: a vegan doesn't intend on eating their wallet or belt, but they won't buy genuine leather goods for ethical reasons. Thus, a vegan belt. For the same reason, a vegan would avoid animal fat based soaps.
Still humorous though, reminds me of the bleach drinking memes.
Considering all the different chemicals used in its manufacture, it is entirely possible that an iPhone isn't vegan.
Depending on how strict you are, plastic isn't vegan. The crude oil used could be considered an animal byproduct, as it is possibly derived from prehistoric animals ;)