The battery in the iPhone 17 Pro Max is physically larger, leading CNET managing editor Patrick Holland to say in his review that it delivers «the best battery life of any phone that CNET has ever tested.» But more power cells aren’t the only contributing factor, and longer battery life isn’t just for the newest iPhone models.

A new software feature in iOS 26 called Adaptive Power also contributes to improved battery life. It’s enabled by default on Apple’s latest phones, but also available on older models that support Apple Intelligence.

Currently, the iPhone uses as much power as it needs to perform its tasks. You can extend battery life by doing a number of things, such as decreasing screen brightness and turning off the always-on display. Or, if your battery is running low, you can turn on Low Power Mode, which limits background activity, like fetching mail and downloading data, and dims the screen to help extend battery life. Low Power Mode also kicks in automatically when the battery level reaches 20%.

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If Low Power Mode is the hammer that knocks down power consumption, Adaptive Power is the scalpel that intelligently trims energy savings here and there as needed. Based on Apple’s description that accompanies the control, the savings will be felt mostly in power-hungry situations such as recording videos, editing photos or even playing games.

Apple says Adaptive Power takes about a week to analyze your usage behavior before it begins actively working. And it works in the background without needing any management on your part. 

Here’s how Apple describes it in the iPhone user guide: «It uses on-device intelligence to predict when you’ll need extra battery power based on your recent usage patterns, then makes performance adjustments to help your battery last longer.»

Which iPhone models can use Adaptive Power?

The feature uses AI to monitor and choose when its power-saving measures should be activated, so that means only phones compatible with Apple Intelligence get the feature. These are the models that have the option:

• iPhone 17
• iPhone 17 Pro and iPhone 17 Pro Max
• iPhone Air
• iPhone 16 and iPhone 16 Plus
• iPhone 16 Pro and iPhone 16 Pro Max
• iPhone 16e
• iPhone 15 Pro and iPhone 15 Pro Max

Although some iPad and Mac models support Apple Intelligence, the feature is only available on iPhones.

How to turn Adaptive Power on

Adaptive Power is on by default on the iPhone 17, iPhone 17 Pro, iPhone 17 Pro Max and iPhone Air. For other models, you must opt in to use it. In iOS 26, you’ll find the Adaptive Power toggle in Settings > Battery > Power Mode. To be alerted when the feature is active, turn on the Adaptive Power Notifications option.

Adaptive Power sounds like an outgrowth of Gaming Mode, introduced in iOS 18, which routes all available processing and graphics power to the frontmost app and pauses other processes in order to deliver the best experience possible — at the notable expense of battery life.

What does this mean for your charging habits?

Although we all want as much battery life as possible all the time, judging by the description, it sounds as if Adaptive Power’s optimizations will not always be active, even if you leave the feature on. «When your battery usage is higher than usual» could include a limited number of situations. Still, considering that according to a CNET survey, 61% of people upgrade their phones because of battery life, a feature such as Adaptive Power could extend the longevity of their phones just by updating to iOS 26.

I also wonder whether slightly adjusting display brightness could be disruptive, but in my experience so far, it hasn’t been noticeable. Because the feature also selectively de-prioritizes processing tasks, the outward effects seem minimal. When it’s activated on my iPhone 16 Pro, the only indication was the Adaptive Power alert that appeared.

We’ll get a better idea about how well Adaptive Power works as more people adopt iOS 26 and start buying new iPhone models. Also, remember that shortly after installing a major software update, it’s common to experience worse battery life as the system optimizes data in the background; Apple went so far as to remind customers that it’s a temporary side effect.