Apple‘s (NASDAQ: AAPL) post-earnings sell-off was no surprise. For the first time in 13 years, revenue contracted, with iPhone sales falling sharply. However, lost in the chatter was the key to what could be renewed growth down the road: The company’s services segment grew 20% to $6 billion in sales in the quarter, as CEO Tim Cook touted the “incredible strength of the Apple ecosystem and our growing base of over 1 billion active devices.”