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In a recent YouTube video, Chinese tech reviewer Geekerwan conducted an extensive battery test on a series of Apple phones, including the iPhone 15 and 16 Pro Max models.
Geekerwan discovered that the batteries lasted longer on iOS 18 than iOS 17, offering a potential boost for battery-conscious users.
iPhone 15 Pro Max Gains Extra Hour of Battery Life with New iOS Update
Geekerwan’s review tested the iPhone’s battery by simulating regular activities, such as texting, voice, and video calls through WeChat, web browsing, using Douyin (the Chinese version of TikTok), and gaming with Genshin Impact.
While the iPhone 16 Pro Max took the crown for battery performance, lasting 10 hours, the real standout was the iPhone 15 Pro Max, which saw an impressive improvement with iOS 18.
The iPhone 15 Pro Max improved battery life after upgrading from iOS 17 to iOS 18.
Previously, it lasted 7 hours and 56 minutes under heavy use, but with iOS 18, its battery life increased to 9 hours and 2 minutes, gaining over an hour.
Similarly, the iPhone 15 Pro also experienced an enhancement, extending its usage time from 6 hours and 22 minutes to 6 hours and 55 minutes after the upgrade.
Geekerwan explained that iOS 18’s improved battery life comes from how the system manages the phone’s CPU.
A CPU (Central Processing Unit) is the main component in a device that processes instructions and performs tasks, acting as the “brain” of the computer or smartphone.
In iOS 18, the system adopts a more gradual approach to CPU power management. Unlike previous versions, it no longer instantly boosts performance to higher levels when tasks are initiated. Instead, this delayed boost enables the phone to consume less power during typical activities such as texting and browsing, resulting in significant battery conservation.
Geekerwan credits iOS 18’s better optimization of the CPU’s efficiency and performance cores, combined with more intelligent clock speed management, for the extra battery life.
These power management improvements align with Apple’s promise during their WWDC keynote, but real-world testing like Geekerwan’s highlights the tangible effects.
As promising as these results are, it’s still uncertain how they will affect day-to-day usage for other iPhone models. Further testing is needed to confirm similar improvements across the lineup. Nonetheless, iPhone 15 Pro Max users can expect longer-lasting performance thanks to the new iOS update.
