Understanding IOS Versions For Secondhand IPhones: What You Need To Know

Introduction

 

Buying a secondhand iPhone? Knowing which iOS version it supports is crucial for performance and features. This guide breaks down system compatibility, upgrade risks, and hidden limitations like AirDrop differences.

 

1. Which iOS Version Does Your iPhone Support?

 

Every iPhone model has a maximum iOS version it can run:

iPhone 6s/SE (1st gen): iOS 15 (originally iOS 9).

iPhone 7/8/X: iOS 15–16.

iPhone XR/11 and newer: iOS 189.

Use Apple's official IPSW checker or third-party sites like ipsw.me to confirm.

 

2. New Features vs. Performance Trade-offs

 

New iOS versions add cool tools but may slow down older phones:

iOS 18's Custom Home Screen: Fun for newer iPhones, but causes lag on iPhone 8/X9.

Battery Drain: Older batteries degrade faster with background AI tasks (e.g., photo analysis in iOS 18).

 

3. Feature Restrictions by Hardware

AirDrop: iPhones without the U1 chip (pre-2019 models) can't use precision sharing.

Apple Intelligence: Requires A17 Pro chips (iPhone 15 Pro only). Older devices miss AI-powered photo edits and Siri upgrades.

 

4. Should You Upgrade?

For iPhone X or newer: iOS 18 is safe and adds useful tools like App Lock.

For iPhone 7/8: Stick to iOS 15–16 for smoother performance.

Downgrading: Possible via recovery mode, but only if Apple still signs the older iOS version5.

 

Conclusion
Always balance new features with your iPhone's age. A secondhand iPhone 11 on iOS 18 works great, but an iPhone 7 is better off staying on iOS 15. Check compatibility, backup data, and enjoy your device!