iPhone 18 Pro Review: All About that Chip
In a Nutshell
The iPhone 18 Pro is essentially an "S" update with the standout feature being its A20 Pro chip on a 2-nanometer process that delivers both major performance gains and efficiency improvements through a new vapor chamber cooling system. The most notable camera addition is a variable aperture lens that can adjust from f/1.48 to f/4, giving users creative control over depth of field and light intake. Battery life reaches new highs through the chip's efficiency rather than capacity increases, while charging speeds improve to 45W, with the phone otherwise maintaining the same 48-megapixel triple-camera system and design language from the previous generation.
These notes were generated by AI and may contain inaccuracies.
The iPhone 18 Pro is essentially an iPhone 17 Pro with a chip update, a camera upgrade, and better battery life, plus new colors. While this represents what would traditionally be called an S update, the device is actually underrated despite the perception of minimal changes.
The Pro iPhone has gone under the radar for two straight years while Apple tested riskier ideas on other models. Last year the iPhone Air stole attention, and this year the first folding iPhone called the Duo is taking focus. The flagship Pro iPhone hasn't had a groundbreaking feature in over a decade, as those appear in other models, but it remains simply the best iPhone they make with quiet improvements over time.
The camera system features the same three 48-megapixel cameras as the 17 Pro: a 48-megapixel primary camera, 48-megapixel ultrawide, and 48-megapixel 4x telephoto. The main camera now includes a variable aperture lens, which is a significant departure from the fixed aperture lenses that have been standard in iPhones and most smartphones except Samsung models.
Fixed aperture lenses display a single f-stop like f/2.2, f/2.0, or f/1.8. The variable aperture on the 18 Pro opens to a maximum of f/1.48 and can stop down to f/1.8, f/2.8, or f/4. Third-party apps can access infinite stages for smooth transitions. The lower the f-number, the larger the aperture and more light reaches the sensor, though stopping down increases sharpness and depth of field.
The variable aperture provides subtle but meaningful control over image characteristics. At f/1.48, more light enters for faster shutter speeds and lower ISOs in low light, while stopping down to f/4 increases the plane of focus and sharpness. The six aperture blades create artistic starburst shapes when stopped down. Auto mode typically defaults to f/1.48 or f/1.8 to maximize light intake.
While the difference between f/1.48 and f/4 may not be immediately obvious to casual users, these Pro tools give creative control over image elements. The variable aperture feature will become more valuable as iPhone sensors grow larger, similar to how it helps with the massive 1-inch sensors in other phones where depth of field can be too shallow.
Apple added more granular Pro controls to the camera app on Pro phones, which makes a bigger difference to user experience than hardware changes. The stock camera app now allows customization of the control bar to include shutter speed, format, manual focus, and manual white balance. Previously, users relied on third-party camera apps to access full camera capabilities.
Suggestions for further Pro improvements include adding a Rec. 709 preview while recording log video and enabling 8K video recording at 30fps, especially given the 48-megapixel sensor and new storage limit settings in iOS 27.
The iPhone 18 Pro and 18 Pro Max contain the new A20 Pro chip built on a 2-nanometer process alongside the simultaneously announced M6. The chip name and phone naming are out of sync, with the 18 Pro using the A20 chip while the 19 would presumably use the A21.
The 2-nanometer architecture moves DRAM off the CPU and places it adjacent, allowing a new 3x surface area vapor chamber to cool the CPU directly. This design enables both significantly better performance and efficiency in a single chip update, which is unusual for S updates that typically offer either performance or efficiency gains, not both.
The chip reaches M1 and M2 level performance, which matters for heavy gaming sessions and extended 4K video shooting in hot conditions. The vapor chamber and connected mid-frame provide better cooling than previous generations. The doubled neural engine improves on-device processing, making Siri noticeably faster even compared to the iPhone 16 which was designed for AI tasks.
The A20 Pro represents a new 2-nanometer node that proves Moore's law continues, approaching transistors the size of individual atoms. This architecture would be particularly powerful in the MacBook Neo, which currently uses a binned A18 Pro with 8GB RAM, as the A20 Pro with 12GB RAM would essentially match M1-level performance.
The 18 Pro achieves the longest battery life ever in iPhones through efficiency gains from the 2-nanometer architecture rather than a larger battery. The 18 Pro matches the battery life expectations of the 17 Pro Max, delivering a day-and-a-half of use without overnight charging and potentially stretching to two days with light usage, despite including high-brightness use, photo taking, and two hours of daily CarPlay.
The battery capacity is only about 3% larger than the previous generation. The Pro Max has approximately 10% larger battery capacity than last year's model, around 5,500 milliamp-hours. Actual capacities are 4,056 milliamp-hours for the Pro and 5,391 milliamp-hours for the Pro Max in European models with SIM trays, with US eSIM-only versions being slightly larger.
Charging speeds improved significantly, with the phone pulling 45 watts from a 67-watt charger for extended periods. The claimed seven hours of video playback after five minutes of wired charging appears accurate. The C2 modem contributes to efficiency and battery life improvements.
New colors include burgundy, Glacier Blue (light sky blue), and matte black. The matte black shows fingerprints more than expected but remains preferred. The Dynamic Island is smaller due to relocating the infrared Face ID sensor to the top left corner behind the display, allowing three Live Activities instead of two.
The iPhone 18 Pro represents a "tock" update in Apple's tick-tock cycle, following the larger changes in the 17 Pro with its new metal design, thicker chassis, bigger batteries, and camera plateau. The 2-nanometer chip provides the main improvements, while the variable aperture camera offers subtle current benefits with future potential as sensors evolve.
The phone is expensive but delivers exactly what was expected from the Pro line, which receives slow, careful evolutions rather than risky new features. The value lies in this predictable refinement of the best iPhone available.
Keep Marques Brownlee in your library
Save the videos and channels worth coming back to, and find them again in one place.
