Check out Apple’s prototype iPhone 14 Pro with haptic feedback buttons from ‘Project Bongo’

In a recent video, Apple Demo provided a rare, behind-the-scenes look at an experimental iPhone 14 Pro prototype developed as part of Apple’s now-abandoned “Project Bongo.” This unique device featured a radical departure from Apple’s standard design: haptic feedback buttons intended to replace the mechanical volume buttons found on current iPhones.

The prototype iPhone is notably stripped down, lacking the typical Apple branding and bearing only the “Vesica Piscis” symbol—two intersecting circles Apple often uses to disguise the purpose of its internal devices. This symbol has been used on various Apple prototypes in the past, including early test versions of AirTags.

In this instance, the symbol appears on a device labeled “RANGER-DROP,” suggesting that this particular model was intended solely for drop-testing, a phase where Apple evaluates the structural durability of a design before adding full functionality.

The video reveals that the device lacks critical components, like camera and display connectors, highlighting its role as a “drop-test” model designed to test durability rather than full operation.

Among the prototype’s more novel elements is a unified, haptic-based volume button that merges the traditional volume-up and volume-down buttons into a single, solid-state button. Unlike mechanical buttons, this unified button provides haptic feedback similar to the Force Touch trackpads on MacBooks, intended to simulate the feeling of a button press without any actual physical movement.

Apple reportedly referred to this experimental feedback system as the “Bongo Haptic Engine,” a specialized haptic motor designed to deliver precise, localized feedback when pressing either end of the button. Apple Demo’s close-up footage shows that pressing on specific areas of the button would trigger either volume-up or volume-down commands, with the Bongo Haptic Engine creating the illusion of a distinct press. This design was part of Apple’s broader plan to eliminate moving parts in iPhones, reducing mechanical wear and theoretically improving long-term durability.

Apple’s exploration of solid-state buttons for the iPhone 14 Pro came before the eventual decision to shelve the idea, though reports suggest the feature nearly made it to the iPhone 15 line. Challenges ultimately led Apple to pause this effort; insiders have noted that integrating the haptic button would require an additional power amplifier and two more Taptic Engines within the iPhone’s internal structure, adding both technical complexity and increased costs. Despite these obstacles, Apple’s R&D team continued to refine the concept, testing prototypes like this one, which blend newer and older design elements. Apple Demo describes the device as a “Frankenstein” prototype, with certain elements resembling the iPhone 13 Pro’s internal components, indicating that Apple often builds such hybrid models to limit costs and complexity during experimentation.

Apple Demo’s deep dive reveals that the experimental iPhone 14 Pro prototype was intended not only for structural integrity testing but as part of Apple’s ambitious long-term vision to refine or even remove physical buttons. The drop-test designation suggests that Apple engineers were assessing how well the haptic button system could withstand physical impacts. Prototypes like these are crucial for Apple’s design process, allowing the tech giant to push boundaries while balancing practical considerations of cost and durability.