According to Bloomberg’s Mark Gurman, iOS 26 Public Beta is set to arrive this week. This time, the test will be open to all devices that can upgrade to iOS 26. So, should you upgrade? Let’s discuss which versions are the best fit for different iPhone models and whether you should take the risk of upgrading to iOS 26.

Why Upgrading Isn't Always a Good Idea?

First, let’s talk about why it’s important to consider upgrading and downgrading. Think of your phone as a house. Upgrading means inviting a more advanced “guest” to move in. We don’t know if the old house can accommodate this “big guy.” Especially for beta versions, which are not stable, they can even affect your phone’s battery and performance. If you only have one phone, my advice is to wait until the system is mature before upgrading. Don’t follow the trend blindly.

As for downgrading, it can be challenging for some users because it requires certain manual skills. If you don’t know how to back up your data, you may not be able to downgrade after upgrading. If Apple has stopped signing the old version, you're locked in, and there's no turning back.

iPhone 11

Recommended: iOS 16.3

-Stable, efficient, minimal bugs

Already upgraded?

-iOS 17.5 is your safest fallback

iPhone 12

Best version: iOS 16.3

-Excellent for battery and daily use

iOS 17 user?

-Stay on 17.7.1

Already on iOS 18?

-18.0.1 is currently safe for main use

iPhone 13

Go with iOS 16.3

-stable and efficient, with solid battery performance

Upgraded to iOS 17?

-Stick with 17.7.1

Already on iOS 18?

-18.0.1 is usable, but 16.3 is still better overall

iPhone 14

Best match: iOS 16.6

-Great system fluidity, especially on Pro models

On iOS 17?

-Use 17.3.1, solid in both performance and thermal control

iPhone 15

Stay on iOS 18.1.1

-Exclusive tuning for iPhone 15 series

Already upgraded to 18.3?

-It’s decent, but stop there unless you really need newer features

iPhone 16

Best version: iOS 18.3

-Stable, battery-optimized, most bugs fixed

-18.1.1 is also fine, but not as smooth under load

Of course, for new devices, there may be more compatible versions in the future. Upgrading is easy, but without backups or Apple’s signature for older versions, downgrading might become impossible. So, before updating, make sure to check the signature and back up your data with 3utools.