Here's the real star of Apple's record breaking quarter

To say Apple had an amazing fourth quarter would be an understatement. It announced record breaking iPhone sales (74.5 million in Q4 2014) and generated more profit in a single quarter ($18 billion) than any other company in history.

But while CEO Tim Cook has been credited with proving all the iPhone skeptics wrong, Above Avalon's Neil Cybart (via Daring Fireball) noted how Apple's smashing quarter proves Williams has been doing a fantastic job.

Williams is in charge of Apple's supply chain, which means he's a large part of the reason Apple was even able to produce enough iPhone units to break its own records. This includes maintaining relationships with suppliers such as Foxconn and negotiating supplier contracts.

Apple faced severe supply constraints with the iPhone 6 Plus when it launched in September, too, which makes Apple's numbers under Williams' oversight even more impressive.

But it's not just production and operations that Williams manages - he's also in charge of the quality behind those products. As Cybart points out, that kind of job requires hours of brainstorming and spending time with the products to understand the best way to produce them in an efficient way.

Cybart goes as far as to call Williams "CEO material." Bloomberg Businessweek's Brad Stone called him "Tim Cook's Tim Cook," getting at the idea that he's Cook's right hand man.

Williams has been leading Apple's mobile operations ever since the first iPhone was announced in 2007, and before then with the iPod. And now, his next venture will be the Apple Watch, which Cook put him in charge of.

"We want to make the best product in the world," Williams said to Stone. "One of our competitors is on their fourth or fifth attempt, but nobody is wearing them."