Project Bongo and the future of haptic technology at Apple

Behind every innovation lies a journey of ideas, experimentation, and sometimes, roadblocks. That’s precisely the story of Project Bongo—Apple’s once-forgotten attempt to revolutionize the way we interact with our devices. If you’ve ever wondered what could have been and might yet be, you’re not alone. Many Apple fans were both intrigued and puzzled when the existence of Project Bongo first surfaced.

The concept originated in 2022, when Apple was developing a new kind of button—one that dispensed with traditional mechanical mechanisms in favor of solid-state haptic feedback technology. The aim? To deliver a more seamless, tactile experience without compromising the elegance or durability of their hardware. It was a bold step toward improving the iPhone’s form and function, and also toward making the premium “Pro” lineup feel distinctly more advanced than base models.

Internally referred to as “Project Bongo,” this design centered around replacing physical volume and power buttons with a sophisticated haptic alternative. Instead of clicking, users would feel simulated tactile feedback when pressing—thanks to a dedicated haptic engine built into each button. Think of it as the same magic that powers the MacBook’s Force Touch trackpad, but in a much smaller, more complex form factor.

This wasn’t a casual experiment tucked away in a lab. According to insiders and leaks, Apple’s engineers invested heavily in bringing Project Bongo to life, going as far as building fully functional prototypes. For a while, it looked like the iPhone 15 Pro would feature these cutting-edge buttons.

However, early 2023 brought an unexpected twist. Amid a whirlwind of development stages like EVT (Engineering Validation Test) and DVT (Design Validation Test), Project Bongo was abruptly removed. Concerns over performance and potential hardware failures led Apple to shelve the design, leaving many to assume the project was dead in the water.

The story doesn’t end there. Unbeknownst to the public at the time, Apple quietly filed a patent for the Bongo technology in September 2023. This move—revealed only in April 2025—signals something more than mere afterthought. It shows that the concept, though challenged by technical hurdles, still holds promise in Apple’s long-term vision.

For anyone who has felt the sting of a promising idea being shelved, this revelation might bring a flicker of hope. It reminds us that innovation is rarely linear. Sometimes, the most forward-thinking ideas need time to catch up with feasibility, reliability, and user readiness.

At the heart of Project Bongo lies its remarkable haptic button module—a feat of compact engineering that merges mechanical precision with subtle software coordination. If you’ve ever experienced the click of a virtual button, like the pressure-sensitive home button on earlier iPhones or the gliding silence of a MacBook’s Force Touch trackpad, you already have a sense of how advanced haptic feedback can reimagine physical interaction. But what Apple attempted with Bongo goes even deeper.

The magic starts with a core component known as the Bongo Haptic Engine. Unlike earlier iterations of haptic modules, which were generally centralized in a device, the Bongo approach localized the feedback directly under the button surface. That way, when you pressed the haptic volume or power button, the sensation didn’t just come from somewhere within the phone—it originated right under your finger. This tiny motor, powered by a ferromagnetic solenoid system, is capable of producing feedback that feels surprisingly authentic.

To detect the press itself, Apple engineered something quite clever. The button module incorporates a system of flexures—small, bendable structures that compress slightly under pressure—and multiple strain gauges, which are sensors that pick up these subtle shifts. When a user presses the button surface, the strain gauges detect the mechanical deformation and generate an electric signal. This signal is instantly passed on to the Bongo Haptic Engine, which then responds with a vibration optimized to mimic the feel of a tactile button press.

In terms of responsiveness and sensory feedback, this closed-loop system creates a smooth and highly convincing button experience. And because there are no moving parts in the traditional sense—no springs, hinges, or wear-prone components—Apple’s engineers believed the entire system would not only modernize the form factor, but also improve long-term durability and resistance to dust or water ingress.

• Input Detection: Flexures and finely tuned strain gauges convert mechanical press into an electrical signal.
• Signal Processing: An onboard processor detects the press event and triggers the haptic mechanism.
• Haptic Output: A precise oscillation of the solenoid emits a “click” sensation under your fingertip.

What set this apart from existing technology was Apple’s commitment to nuance. Instead of static feedback—where every press feels the same—Project Bongo allowed for adaptive haptics. Depending on how long or firmly a user pressed, the feedback could shift, becoming stronger or more subtle. The system was designed to be intelligent, recognizing different levels of intent and adjusting the tactile response accordingly. Imagine lighter taps for single clicks and firmer presses for toggling functions—a truly dynamic interaction model.

Apple’s patent documentation even mentioned the possibility of customizing the feedback to match user preferences or contextual needs, like quiet operation in Do Not Disturb mode or extra assurance when activating a critical function like powering down the device.

It’s worth acknowledging the ambition packed into such a small space. The haptic button module had to be ultra-thin to fit within the slim profile of devices like the iPhone Pro series, all while maintaining necessary strength and delivering reliable feedback. It’s no wonder that technical hurdles—like inconsistency in press detection and false touches—ultimately delayed its release. But the technology, as described in Apple’s filings and tested in prototypes, still represents a significant step forward in hardware evolution.

For those who eagerly follow tech advancements, especially those who crave that satisfying click, even sans movement, it’s fascinating to see just how far Apple tried to push the boundaries of user interaction. Though this version of Bongo never made it to consumers, its laser focus on blending form with emotional feedback could very well become a standard in future device design.

Once Project Bongo was up and running inside Cupertino’s walls, Apple didn’t just dream about innovation—they built it. Prototypes featuring the solid-state haptic buttons weren’t theoretical concepts buried in whitepapers—they were real, tangible iPhones that internal teams held, tested, and pushed to their limits. These devices made it well into Apple’s prototype development stages, with iterations of the iPhone 15 Pro Max showcasing fully integrated Bongo modules during EVT (Engineering Validation Test) and early CRB (Configuration Review Build) phases. For a moment in early 2023, it genuinely seemed like we’d be unboxing iPhones with silent, seamless haptic inputs by the fall.

According to people close to the project, the hardware was not only functioning but felt “incredibly satisfying” during early hands-on evaluations. Testers reportedly described the buttons as so convincingly tactile that they forgot they weren’t physically moving parts. That’s the magic of great design—when it disappears into the experience.

But internal testing is where Bongo’s journey hit a rough patch. While the user experience was compelling, the system’s reliability under variable conditions didn’t meet Apple’s famously high standards. Engineers encountered issues with false activations and inconsistencies across different environmental tests—problems that could lead to frustrating user interactions with something as basic, yet essential, as the power button. This feedback loop between performance and expectation is as rigorous as it gets inside Apple’s development pipeline.

As the team transitioned from EVT into the more critical DVT (Design Validation Test) phase, where more thorough assessments simulate real-world use, these concerns became more pronounced. Apple’s internal metrics reportedly flagged degradation in sensor sensitivity over time. In some cases, buttons responded too early or failed to register hints of pressure. Considering the role these buttons play in emergency SOS calls or restarting a device, there was no margin for error.

In April 2023, the decision was finally made to cut the haptic buttons from the iPhone 15 Pro lineup. It wasn’t a lightly made call. In fact, the removal came late in the production pipeline, prompting last-minute design reversions and causing ripple effects across Apple’s manufacturing and logistics ecosystem. For those inside Apple who championed the project, it was a hard pill to swallow—but one grounded in the company’s overarching philosophy: never ship something that isn’t as close to perfect as possible.

Interestingly, Project Bongo didn’t completely disappear. In the months that followed, Apple continued experimenting with the design on iPhone 16 prototypes. There were even earlier sightings on rugged development builds of the iPhone 14 Pro, suggesting the company had been following this path longer than initially believed. It’s rare for a feature to straddle this many generations of hardware testing without going to market, which underscores both Apple’s commitment to the idea and the depth of the technical challenges they still face.

And for those wondering if these prototypes ever left Apple’s labs—words turned into images when early 2025 reports from sites like AppleInsider published photos of the EVT-stage iPhone 15 Pro Max with Bongo hardware exposed. It was a rare public glimpse into Apple’s iterative process, and a testament to how seriously they pursued this new form of tactile interaction.

Every prototype left behind is a stepping stone. While Bongo didn’t survive the climb to retail release, it forged a path that Apple could revisit as materials improve, production processes mature, and user expectations shift. The fact that Apple went as far as patenting the technology after its removal strengthens the idea that Bongo isn’t gone—it’s just on pause. And in Apple’s world, a pause often precedes a surprising comeback.

• EVT and DVT tested: Functional Bongo buttons made their way into late-stage iPhone 15 Pro prototypes.
• Hardware failure rates discovered: False touches and sensor drift led to critical usability concerns.
• Technology shelved, not scrapped: Bongo survives through continued R&D and now in a publicly revealed patent.

For those who get excited about the feel of brilliant technology—or frustrated by close calls like this—it’s worth remembering that even shelved projects can fertilize future growth. The story of Bongo is still being written, and like many of Apple’s innovations, some of the best chapters may come quietly, before we even realize they’ve arrived in our hands.

So what comes next? If you’ve followed Apple for any length of time, you know they rarely let promising technology go to waste. The reappearance of Project Bongo in a formally published patent means it’s very much alive within Apple’s ecosystem of ideas, even if it’s been held back from the consumer spotlight—for now. But here’s where things get interesting: Apple’s patent isn’t just a narrow blueprint for iPhone buttons. It invites possibilities across a broad range of devices—many of which you might already have in your everyday life.

First and foremost, the iPhone is still the most likely candidate to debut a refined version of the Bongo haptic system. If Apple continues to develop its solid-state button tech, future “Pro” models may reintroduce the idea—this time with improvements that address the previous reliability concerns. Given the benefits of better sealing, a thinner frame, and fewer points of mechanical failure, the move would align perfectly with Apple’s vision for durability and elegance.

But it doesn’t stop with smartphones. Apple’s own wording suggests that the haptic module could extend to “various electronic devices,” including tablets, smartwatches, and even accessories like the Apple Pencil. Imagine an Apple Watch with solid-state side buttons that won’t wear out or take on water over time. Picture an Apple Pencil with customizable haptic gestures—a squeeze or press could trigger brush-switching in design apps or execute commands in note-taking software. This is about more than button replacement. It’s about interaction redefined.

There’s also provocative potential in Apple’s wearable and AR hardware. Devices like the Apple Vision Pro, still early in their lifecycle, could benefit from tactile controls without adding bulk. Imagine gesture-based interactions that feel grounded and responsive through subtle haptic pulses. In such immersive environments, the role of physical feedback becomes not just delightful—it becomes essential for spatial orientation and intuitive use.

• Apple Watch: Integration of durable, solid-state Digital Crowns or side buttons protected from ingress and long-term wear.
• Apple Pencil: Enhanced gesture support via tactile cues—grip-based expression, customizable presses for tool shifts.
• iPad: Solid-state volume buttons with feedback tuned for accessibility and varied grip orientations.
• Vision Pro: Haptics that complement gesture controls for a more immersive, responsive augmented reality experience.

It’s clear that Project Bongo was more than a one-device experiment—it was a modular concept with transformative potential across Apple’s ecosystem. But what’s equally clear is that Apple won’t rush it. That same deliberate approach that paused Bongo’s inclusion in the iPhone 15 Pro is likely shaping its next evolution. For users, this means when the technology returns, it may not simply come back—it could come back smarter, more refined, and more deeply integrated than we’ve imagined.

If you’ve ever held a new device and been surprised by how natural it feels—like it knew what you wanted before you did—that’s Apple at its best. Project Bongo, whether we see it next year or three years from now, has the DNA of that principle. It’s quietly signaling a leap toward smarter hardware that understands you not just through pixels and processors, but through touch, pressure, and subtle, responsive feedback.

So if you’re hopeful, you’re not alone. The tech may have stumbled, but it’s not lost. Apple has a long history of circling back on rough-edged ideas and turning them into polished cornerstones of the future. As always, the real magic will happen when we’re not expecting it—when the familiar click of a button feels brand new, and we won’t even notice the mechanics are missing.