Under Tim Cook, Apple attained $4.6 trillion market capitalisation, built an efficient supply chain network that sold over three billion iPhones, and effectively stewarded Steve Jobs’ legacy. While Mr. Cook’s era will be remembered for scale and operational efficiency, those twin markers of growth could not have been accomplished without an underlying solid product line-up. That is precisely where hardware engineering comes in — the unit headed by John Ternus.
Mr. Ternus joined Apple’s cinema display team in 2001 after a stint designing VR headsets at a small firm called Virtual Research Systems. His first project at Apple was the Cinema Display monitor. The company had just launched the iPod and was basking in its glory. But consumers were shifting to cellular devices as the world was coming online.
Apple needed a product to capture the trend as Finnish handset maker Nokia’s 3310 mobile phones — shipped with small, green-lit display screens — were selling like hot cakes. While these devices were solid, their functionality was limited. Yet they filled the gap by increasing storage space that could be used by buyers to store files that included music. This was eating into the music player market.
With the help of French computer scientist Jean-Marie Hullot, who wrote programmes for the original Macintosh and operating system for a smartphone, Apple built the iPhone, a device that redefined mobile telephony by ditching physical keypad — a design change that elbowed BlackBerry aside in the high-end mobile market, showcasing Apple’s display hardware prowess.
A seat at the table
In 2010, Apple unveiled iPad, a device that further solidified its position in making an industry-leading consumer hardware. In 2013, the same year it launched iPad Air, the company elevated Mr. Ternus as vice president of hardware engineering, a move that recognised his contributions by enhancing his span and control over product lines.
By 2021, he was made the global head of hardware engineering, reporting to Mr. Cook directly and effectively running engineering for every major product line Apple sells.
Apple’s own succession language credits him with being instrumental is introducing multiple new product lines, specifically AirPods and iPad. Mr. Ternus has also been known for pushing for the creation of iPadOS back in 2019 as a distinct operating system rather than leaving the iPad running a stripped-down version of iOS — a decision that let the product’s hardware capabilities actually matter.
But the clearest preview of the Ternus era is the iPhone Air, which launched in 2025 as Apple’s thinnest iPhone ever. It gave a glimpse into how Mr. Ternus builds and operates. Rather than simply shrinking an existing iPhone, his team coordinated closely with hardware technologies team led by Johny Srouji to fit pro-level performance into a dramatically thinner chassis.
That meant a new A19 Pro chip, Apple’s N1 wireless chip, and — most notably — the C1X modem, Apple’s second-generation in-house cellular modem, which matters enormously for a phone with a thinner, smaller battery.
The iPhone Air shows how Mr. Ternus’s hardware engineering teams and Mr. Srouji’s chip teams work in lockstep from the earliest stages of a product’s design. The modem, the processor, and the physical chassis were engineered together rather than in sequence.
The silicon factor
Mr. Srouji is central to understanding how Apple builds devices today. He joined Apple in 2008 and helped develop the A4, the company’s first custom chip, and has since led the build-out of an entire in-house silicon operation. Today, the A-series chips powers the iPhone and iPad, the M-series chips run every Mac, iPad Pro, and Vision Pro, and the C-series powers the cellular modems and the N1 networking chip handles Wi-Fi, Bluetooth, and Thread.
The modem effort in particular has been a multi-year undertaking. Apple acquired Intel’s smartphone modem business in 2019 after its legal battle with Qualcomm, and spent roughly six years building an internal baseband engineering team before the C1 finally shipped.
Apple’s intends to bring custom modems to more of its line-up over time — though its flagship iPhone 17 Pro models still ship with Qualcomm’s Snapdragon X80 modems, suggesting the transition isn’t complete.
As part of the leadership reshuffle around Mr. Ternus’s promotion, Mr. Srouji’s role has also expanded. As Apple’s chief hardware officer, he will oversee both hardware technologies and hardware engineering teams — groups run by him and Mr. Ternus respectively.
In effect, the chip design and physical product engineering functions — long closely coupled but organisationally separate — now sit under one executive, reporting to the CEO. Such a deeply integrated hardware division is likely to deliver a solid line up of premium products.
There is a lot of chatter online that Apple could unveil their first foldable phone at Cupertino on September 9. We won’t know for sure until its official. But the rumour mill has been churning this out for at least a month now. Apart from a foldable phone, under Mr. Ternus, the company would likely build a new product line-up in the smart-glasses segment, and also expand capabilities of Vision Pro.
The software alignment
But beyond hardware, Mr. Ternus has an important task of integrating software developments at Apple with the products built by Mr. Srouji’s team. Coming from a botched AI launch that culminated in a $250 million class-action settlement in May, the company needs to show that its user interface is as much class-leading as its hardware.
Apple Intelligence arrived later than competing offerings, a promised overhaul of Siri is delayed, and Apple has ultimately turned to Google to help power some of its AI features rather than relying solely on in-house models. Mr. Cook’s tenure was defined by operational excellence and disciplined expansion into new hardware categories; what it didn’t produce was a signature AI product to match the iPhone or Mac.
That’s the problem now sitting on Mr. Ternus’s desk. He inherits a company with an enormously profitable hardware business that includes product lines he personally built, but one with no clear AI strategy of its own. How he integrates the company’s software capabilities into the devices it makes in the age of AI agents will be tracked closely.
Published – September 03, 2026 12:21 pm IST
