That surge led Apple to its most profitable quarter ever. In September, Apple introduced redesigned iPhones: a thin model called the iPhone Air and an overhauled iPhone Pro, which features a raised bump across its back. Those changes, coupled with robust holiday spending, continued to lift iPhone sales in the quarter. Apple reported its sales in China rose 38 per cent to $25.5 billion in the quarter. In October, Apple said it expected to pay about $1.4 billion in the quarter.