Apple Tweaks iPhone 16 Pro Action Button Design as Early Development Continues

Recent iPhone 16 Pro prototypes seen by MacRumors indicate that Apple has again tweaked the design of the Action button, and now it looks much like the Action button found on the iPhone 15 Pro. Apple has been toying with the size and design of the Action button for the ‌iPhone 16 Pro‌, but in the latest “Proto2” development stage, the company is sticking with a tried and true design.

During the different ‌iPhone 16 Pro‌ development stages, Apple has tested four button configurations and two sizes for the Action button.

• Unified volume button with small Action button
• Unified volume button with large Action button and new Capture button
• Separate volume buttons with large Action button and Capture button flush with frame
• Separate volume buttons with small Action button and Capture button flush with frame (current)

The earliest known prototypes of the ‌iPhone 16 Pro‌ had a unified volume button and small multi-purpose Action button, both on the left side, with a power button on the right. This design was initially developed as part of Project Bongo, which was an attempt to bring haptic buttons the ‌iPhone 15 Pro‌. While the project was ultimately canceled due to unsatisfactory test results and high hardware failure rates, parts of the Bongo design, namely the unified volume button, found their way onto early designs of the ‌iPhone 16 Pro‌.

The second prototype variant of the ‌iPhone 16 Pro‌ also used a unified volume button, but it had a larger Action button that was close in size to the volume buttons. This prototype also had an additional “Capture button” on the right side below the power button.

Later prototypes (pictured above) featured separate volume buttons rather than the unified button design. With these more recent units, Apple planned to include a capacitive Action button and Capture button, both of which were flush with the frame and featured force sensor technology.

With the most recent “Proto2” design, Apple has once again changed the Action button. Apple has now adopted a smaller Action button that mirrors the Action button on the ‌iPhone 15 Pro‌, doing away with the larger, flush look. While it is currently unclear how this affects the future of Apple’s work on a capacitive Action button, a design change as significant as this indicates it has been canceled or postponed for future iPhone iterations.

Although the information presented here accurately describes existing internal designs, it is important to note that additional design changes are always possible, and the information presented here may not reflect finalized design of the ‌iPhone 16 Pro‌.

For additional information on what to expect from the 2024 ‌iPhone‌ lineup, check out our dedicated rumor roundups for iPhone 16 and iPhone 16 Pro.