The Latest iPhone Software Update and What Changed

What the newest iPhone update includes

Apple releases major iPhone updates once a year, usually in September. The most recent version is iOS 18, released in September 2024. It includes changes to how Siri works, new privacy controls for your photos and messages, and updates to the lock screen and control center that let you customize them more.

iOS 18 also introduced Apple Intelligence, a set of AI-powered features that summarize notifications, rewrite emails, and generate images on your device rather than sending data to Apple's servers. These features are available on iPhone 15 Pro and newer models. The update also improved battery life tracking, added new health app features, and changed how notifications appear on your screen.

If you have an older iPhone, you may not be able to install iOS 18. iPhone XS, iPhone XR, and iPhone 11 can install iOS 17 instead, which is the previous major version. Apple typically supports iPhones for five to six years with security updates and new features.

Key Takeaways

iOS 18 is the newest iPhone update, released in September 2024, and includes AI features, privacy improvements, and customization options for your lock screen.
Apple Intelligence features only work on iPhone 15 Pro and newer, so older phones will not get these specific tools even after updating.
You can check which iOS version your phone is running in Settings > General > About, and you can see what new features are available before you update.
Security updates for iOS 18 come out regularly throughout the year, separate from the major annual update, and you should install them as soon as they appear.

How to check your current iPhone version

Open Settings on your iPhone. Tap General, then tap About. Look for the line that says "Software Version" — that number tells you which iOS version you have. If it says 18.0 or higher, you have iOS 18. If it says 17.x, you have iOS 17.

Below the software version, you will see a line that says "Latest Software Version" if an update is available. If that line appears, an update is waiting for you to install. You can also go to Settings > General > Software Update to see the same information and start the read from there.

What changed in iOS 18 that affects security

iOS 18 added Advanced Data Protection, which encrypts more of your iCloud data — including backups, photos, and notes — so that Apple cannot read them even if someone hacks Apple's servers. You turn this on in Settings > [Your Name] > iCloud > Advanced Data Protection. It is optional, but it is the strongest privacy setting available.

The update also changed how apps can access your photos and videos. Instead of giving an app permission to see all your photos at once, you can now let it see only the specific photos you choose. When an app asks for photo permission, you will see a new option to "Select Photos" rather than "Allow Access to All Photos." This means fewer apps can see your entire photo library by accident.

Messages in iOS 18 now support end-to-end encryption for group chats, the same way one-on-one messages have been encrypted for years. This means the content of your group messages is encrypted from the moment you send them until the person receives them, and Apple cannot read them.

Whether you need to update right away

If iOS 18 is available for your phone, you do not need to update when ready. However, you should update within a few weeks. Apple releases security patches regularly, and older versions stop receiving them after a few months. If you wait too long, your phone becomes vulnerable to known security problems that hackers can exploit.

The safest time to update is when your phone is plugged in and connected to Wi-Fi, because the update takes 15 to 30 minutes and uses a lot of battery. Plug your phone in, connect to Wi-Fi, go to Settings > General > Software Update, and tap "Install Now." Your phone will restart several times during the process — this is normal.

If you have an older iPhone that cannot run iOS 18, you can still install iOS 17 or earlier versions. Apple will continue to release security updates for iOS 17 for at least another year, so your phone will remain protected even if you do not have the newest version.

What happens if you skip an update

If you skip iOS 18 and stay on iOS 17, your phone will continue to work normally. Apps will still open, calls will still work, and you can still use your phone for everyday tasks. However, you will not get new features like the customizable lock screen changes or the improved privacy controls in iOS 18.

More importantly, you will stop receiving security updates after Apple stops supporting iOS 17. This usually happens about a year after the new version comes out. Once security updates stop, any new security problem that Apple discovers will not be fixed on your phone, and hackers can use those problems to access your data.

If you have an iPhone that cannot run iOS 18 — like an iPhone 11 or older — you should still update to the highest version your phone supports. Check Settings > General > Software Update to see what version is available for your specific model.

How to see what features are new before you update

Before you install iOS 18, you can read about what changed. Go to Settings > General > Software Update, and you will see a description of the update. Tap "Learn More" to see a longer list of changes. Apple also publishes a full list of changes on its website at apple.com/ios/release-notes.

If you want to know whether a specific feature will work on your phone, check the device requirements. Apple Intelligence, for example, only works on iPhone 15 Pro, iPhone 15 Pro Max, iPhone 16, and iPhone 16 Pro. If you have an iPhone 15 or earlier, you will get the other improvements in iOS 18 but not the AI features.

Frequently Asked Questions

Can I go back to an older iOS version if I do not like iOS 18?

No. Once you update to iOS 18, you cannot downgrade to iOS 17. Apple does not allow this because older versions have security problems that have been fixed in newer ones. If you are concerned about compatibility with a specific app, check whether that app works on iOS 18 before you update.

Will iOS 18 slow down my older iPhone?

iOS 18 is designed to run on iPhones from iPhone XS and newer, so it should not make those phones noticeably slower. However, very old iPhones may run some features more slowly than newer models. If your phone is more than five years old, you may want to check online reviews of iOS 18 on your specific model before updating.

Do I have to turn on Apple Intelligence if I update to iOS 18?

No. Apple Intelligence is optional. If you update to iOS 18 on an iPhone 15 Pro or newer, you can choose not to enable it. Go to Settings > Apple Intelligence to turn it on or off. You will still get all the other improvements in iOS 18 even if you do not use Apple Intelligence.

How often does Apple release security updates for iOS 18?

Apple releases security updates roughly once a month, though sometimes more often if a serious problem is discovered. These updates are smaller than the major annual update and usually install in a few minutes. You should install them as soon as they appear in Settings > General > Software Update.

What if my iPhone is too old to run iOS 18?

If your phone cannot run iOS 18, check Settings > General > Software Update to see which version is the highest your phone supports. Apple will continue to release security updates for older versions for at least a year after the new version comes out. Update to the highest version available for your model to stay protected.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.