The biggest one, IMHO, was a business model shift. Apple treated the end-user (not the carrier) as their customer, and used their clout to put their boot on the

The biggest one, IMHO, was a business model shift. Apple treated the end-user (not the carrier) as their customer, and used their clout to put their boot on the carrier's neck in enforcement of this. No longer were you buying the carrier's phone offering. You were buying Apple's phone (even if from the carrier). Because of this, Apple was able to develop products the end-user wanted to buy, rather than the products the carriers wanted to sell.