Nothing much really, besides the marketing and the rivers of BS that come with the products.
That's just good marketing for you, what apple do best to be fair. They have to sell them, and that's exactly what they do, very well. Who'd have thought putting an 'i' in front of the word phone would have been such a great marketing ploy! It seems stupid, it probably is at face value, but you can't doubt they still sell a shedload of products. If they marketed them like other similar products on the market, I can assure you they would not be anywhere near as popular.