At least in the US market it was revolutionary not because of technical specs, but because it changed the relationship between phone manufacturers and the consumer. Before the iPhone, manufacturers considered the phone service provider to be the customer. The service provider specified what the phone could do, so that the service provider could maximize profit, very much at the expense of the quality of the end-user's experience. Apple, and Apple alone, had the clout to say that they would not cripple their product to satisfy the very short-sighted goals of the service providers. I'm not aware of how things worked in other markets, but in the US that was a revolution.