The more the battery is used, the "buffer" it becomes.

The iOS 26.4 Beta 4 update recorded a strong breakthrough in battery life after 3 days of experience with the appearance of the iOS 18.7.6 patch for older devices.

After exactly 3 days since Apple released Beta 4 of iOS 26.4, the technology community has begun to feel the true stability of this build code ending with the letter “A”.

As an inevitable rule of the iOS operating system, the device usually needs about 48 to 72 hours to complete rearranging the background processes. Actual results after 3 days of experience not only satisfy users who prioritize performance but also bring an extremely positive signal about battery life on new iPhone models.

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iOS 26.4 Beta 4 battery life: The more you use it, the better it gets

The most impressive point in this review is the improvement in battery capacity day by day. During the first two days, the device recorded an average usage of about 5 and a half hours On-screen (SOT) for about 80% battery consumption. However, entering the third day, the system was truly “in shape”:

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Day 3 results: With only 79% battery consumption, the device achieved up to 7 hours and 17 minutes On-screen.
Test task: Users are heavily active on resource-hungry applications such as TikTok, Instagram, YouTube and messaging tools continuously.
Comment: Reaching the milestone of more than 7 hours of use while still having more than 20% battery remaining is an extremely ideal number, showing that Apple has optimized power management extremely well in this Beta 4 version.

To experience the smoothness and durable battery life of the new operating system on the most standard color screen, everyone can refer to the iPhone 17 list here:

Realistic performance and stable Benchmark scores

In terms of performance, experience on the primary iPhone (Primary device) shows that iOS 26.4 Beta 4 operates very smoothly and responsively (snappy). Opening the App Store app, surfing the web, or multitasking all happen instantly, without any lag or dropped frames. Although multi-core CPU scores on Geekbench recorded a stable average instead of breaking records, graphics performance (GPU) remained at a very high level, ensuring the gaming experience and AI video processing were always at their best.

iOS 26.4 Beta 4 after 3 days: The longer the battery lasts, the longer it lasts

In addition, Apple has also officially released the iOS 18.7.6 update (build code 22H320) for older devices that do not support iOS 26. This is mainly an update that focuses on fixing bugs and patching important security holes. Users who are using older iPhones still on iOS 18 are recommended to update immediately to protect their devices against cyber attack risks.

Should I upgrade now?

All in all, iOS 26.4 Beta 4 after 3 days of use has proven its software maturity. With battery life breaking out to 7 hours On-screen and stable performance, this is the most reliable tested version from the beginning of 2026 until now. If you are on older Beta versions, upgrading to Beta 4 immediately is the absolutely right decision to enjoy smoothness and a noticeably cooler device.

Don’t forget to visit Minh Tuan Mobile system to receive support from a team of technicians to check and update the safest software. We are always ready to advise on the latest iPhone 17 and iPhone 16 models with the old Fall – Renew policy with extremely high subsidies for users to confidently master technology!