The new iPhone 15 Pro lineup offers the typical slate of new features designed to persuade customers to upgrade: They’re slimmer and thinner than last year’s crop. The new cameras are professional-grade and the switch to USB-C charging will make your life easier. But one new feature easily stands out: The Action Button. Apple has repurposed its physical mute button on the side of its high-end models into a more customizable tool, allowing users to carry out a handful of commands, from recording a voice memo and taking a picture to turning on the flashlight. The button can also be programmed to launch any app or shortcut, essentially turning it into a remote control or launching pad to gain quick access to something you want on demand. In the days since Apple’s iPhone 15 event at its Cupertino, California, headquarters, I’ve used it to load a variety of apps in a single press, including CNN, Amazon and Instagram. It’s certain the Action Button will become a viable resource for anyone who revisits an app time and time again throughout the day. But it also has the potential to become an even more powerful tool; you could program it to play your favorite playlist, turn on the smart lights in your living room or use it to open the garage door. You could even turn it into a dedicated button to call mom. It builds on iOS’s existing offering of ready-made or custom shortcuts, and Apple is encouraging developers to build other unique shortcuts that other users could activate on the Action Button. The change is subtle but it’s one of the few noticeable tweaks to the iPhone’s design this year. The Action Button is about the same size as the existing button, and users still hold it down to switch between muting and turning on the ringer. Commands are accompanied with visual feedback from the Dynamic Island bar — home to alerts and notifications at the top of the screen. The Action Button update, along with changes in the phone’s charging and camera systems, comes as Apple looks to give consumers more reasons to upgrade their iPhones. Last month, Apple’s sales fell for the third consecutive quarter. iPhone revenue came in at $39.7 billion for the quarter, marking an approximately 2% year-over-year decline, as people update their devices less often. Another selling point to splurge for the iPhone 15 Pro ($1,099) or iPhone 15 Pro Max ($1,199): The phones come with a titanium casing — the same alloy used to build the Mars Rover — making them what Apple calls the thinnest and lightest Pro models to date. Apple’s entry level iPhones, the iPhone 15 and iPhone 15 Plus, cost $799 and $899, respectively. The entire lineup starts shipping on Friday. How it works To program the Action Button, iPhone 15 Pro users can visit the button’s section in Settings, scroll through and select from a series of functionalities — such as flashlight or camera. By picking the shortcuts option, however, users can sift through their list of apps or previously established commands. Once set, there’s a slight learning curve following years of falling into the habit of using the physical button to turn the volume on and off. For this reason, it could take quite a while for some of iPhone’s loyalists to change how they use the device. The Action Button isn’t entirely new; the company unveiled it last year on the Apple Watch Ultra. Apple told CNN it was inspired to bring it to the iPhone after hearing anecdotes from users who said they consistently leave their phone on silent, rendering that button essentially useless. Considering iPhone usage has changed a lot since the iPhone debuted 16 years ago, revisiting a hallmark feature like the mute button was only a matter of time, according to the company. Mixed reception Ramon Llamas, a director at market research firm IDC, believes last week’s announcement is only the first step toward making the Action Button more dynamic. “I’d like to think that the Action Button could be expanded a bit more, like one click will take you to one feature; two clicks takes you to another, and three clicks gets you something else,” Llamas said. “But I think that would be it. Any more than that and you risk launching the wrong app, like Wordle, at the wrong time (when you need your camera the most),” he said. It’s also a strategic way for Apple to make the most of already tight real estate on the device, according to Llamas. Annette Zimmerman, a VP analyst with market research firm Gartner, agrees, noting that “having one button to do exactly one thing isn’t really progressive in a time where everything has multi-functionality and can be programmed.” Although it’s unclear if the Action Button will come to more devices in the future, Apple continues its sweep to create a uniform ecosystem for its consumers. Similarly, Apple is adding a Double Tap feature that allows people to use a finger feature to control the Apple Watch, just months after it showed off a similar gesture on its upcoming Vision Pro mixed reality headset. For now, iPhone 15 Pro users will enjoy playing with the new Action Button. While the feature is not worth the upgrade to iPhone 15 alone, the switch to universal charging, a faster processor and advanced camera capabilities make it a solid package, especially if you haven’t upgraded in the last few years.