For about two decades, the blistering pace of smartphone hardware improvements has driven manufacturing advances. We've made massive engineering improvements in all the components in the latest flagship phones: touch screens, systems-on-a-chip, tiny camera modules, wireless radios and chips and protocols, batteries, and even materials science and industrial design and precision manufacturing. The annual release cycle forced such a fast iteration loop that the original iPhone—or the Blackberry or Clie that came before it—is barely recognizable as a device in the same product category as something like the Huawei Tri-fold Mate XT.
And all these hardware innovations have found their way into other electronics. PCs and laptops use the same chips and screens; drones have gotten way better in leveraging camera and battery tech; categories of smart home devices use either screens or batteries or speakers/microphones, and they're usually reliant on phones for setup and configuration. The vanguard of the smartphone leaves behind a wide technological wake, where multitudes of adjacent gadgets have drafted in its slipstream.
But the age of smartphone hardware innovation is coming to an end. I flagged this possibility almost 6 years ago, that we might have peaked in how much phones can still act as a forcing function for better hardware—simply because they've gotten good enough for most users. The market is completely saturated[1], and there are fewer and fewer reasons to upgrade to a newer model if your current handset still runs with decent battery life. Much like PCs, the hardware has stabilized, and any improvements now come from hardware experiments that run a higher risk of being abandoned in subsequent updates.
Wearables, though, have picked up the slack. Consider how, in the span of a few years, phones added: GPS radios, accelerometers, and NFC chips[2]. In subsequent years after these components' manufacturing matured, phone makers took all that hardware and shrunk it further and shoved the bundle inside of a watch. And then, when the product category proved to resonate around health, proceeded to add even more sensors like oximeters and glucose monitors to the package.
The more obvious direction to take these technical advancements is to continue shrinking the hardware. Smart rings have been around for years, but last year saw a surge in new entrants into the space by both established companies and startups looking to incorporate some of those miniaturized health monitors. Earbuds, too, have gotten increasingly sophisticated; what started as plastic blobs of Bluetooth radios, batteries and speaker drivers have added touch and proximity sensors, wireless charging contacts, and more processors that specialize in everything from wireless connectivity to noise cancellation to real-time translation. AirPods can already take us to the moon.
Another development path is to take the computing bits perfected by phone manufacturing and put them in new form factors that have a chance to replace the phone as next-generation devices. The Humane Pin was one such attempt, but it bit off way more than it could chew and shut down less than a year after launch. The Apple Vision Pro is way too bulky and expensive to be a phone or even a laptop replacement, but it does leverage many of the technologies advanced by iPhones—the processors, iPadOS apps, lidar and cameras—while inventing necessary new ones around real-time sensor processing and super high-res, low-latency displays.
But the wearable with the most potential right now is smart glasses. In contrast to VR headsets that have been commercialized into gaming and metaverse machines, AR glasses have kept their hardware simple and the functionality limited up to this point. There are the Meta Ray-Ban glasses and Snap Spectacles available right now; then, futuristic R&D projects like Meta's Orion AR glasses and rumored prototypes from both Google and Apple. Bridging the gap currently are smart glasses, more functionally analogous to smart watches.
Glasses, though, have the distinct advantage of being worn on the face, with their displays always directly in front of users' eyes. Instead of relying on the solved engineering of high-resolution, capacitive touch screens, the vision systems for glasses require new inventions: eye tracking; spatial and gesture tracking and processing; projecting onto a translucent surface or directly into the eyes. A Kickstarter project is looking to build an MVP of that last technology, while a Finnish startup is leveraging eye tracking to change its lenses' optical focus to make a 21st century bifocal. There are even commercially available glasses experimenting with e-ink displays to optimize their reading experience, which combines a number of my hobbies into one device.
It's now clear that the phone has hit a local, if not absolute, maxima of technological prowess; not to say that there won't be incremental technical improvements still, but I suspect they'll land more like the various gimmicks PC manufacturers have tried in the past 10–15 years to entice laptop enthusiasts to upgrade. Instead, the novel form factors of wearables, plus the amount of component miniaturization opening up new functionalities, make them a prime device category to push hardware advancements for the next decade.