iOS updates bring security patches, performance changes, and new features to your iPhone
A new iOS release is a complete software update that Apple pushes to iPhones and iPads. When you see a notification to update your device, you're being offered a newer version of iOS — the operating system that runs everything on your phone. Each update includes security fixes for vulnerabilities Apple has discovered, changes to how your device performs, and sometimes new features you can use. The version number tells you how significant the update is: a jump from iOS 17 to iOS 18 is a major release with substantial changes, while a move from iOS 18.0 to iOS 18.1 is a smaller update that usually focuses on fixes and refinements.
You don't choose whether to update — Apple controls the schedule and pushes updates to all compatible iPhones at the same time. This is different from Android, where manufacturers and carriers have more control over timing. Apple typically releases one major iOS version per year in September, along with smaller updates throughout the year when security issues need fixing or bugs need patching.
Key Takeaways
- iOS updates arrive automatically as notifications on your phone and include security fixes, performance improvements, and sometimes new features.
- Major iOS releases happen once per year, usually in September, while smaller updates come out throughout the year to fix specific problems.
- Delaying an iOS update leaves your phone vulnerable to security flaws that Apple has already patched in the newer version.
- Your iPhone's age determines how long it receives updates — typically five to six years of support from the release date of your device.
- Updating takes 15 to 45 minutes depending on your phone's storage and internet speed, and you should plug in your device before starting.
Why Apple releases updates so frequently
Security is the main reason. When Apple discovers a vulnerability in iOS — a flaw that hackers could exploit to access your data or take control of your phone — the company writes code to fix it and releases that fix as an update. If you don't install the update, your phone remains vulnerable to anyone who knows about that flaw. This is why security researchers and Apple itself recommend updating as soon as a new version becomes available.
Beyond security, updates also fix bugs that users have reported — apps crashing, battery draining faster than expected, or features not working as designed. Apple also uses updates to improve performance, making your phone run faster or use less power. Occasionally, a major iOS release introduces new features like improved camera controls, new privacy settings, or changes to how notifications work.
What happens to your phone during an update
When you install an iOS update, your phone downloads the new version, installs it in the background, and then restarts. During this process, your data stays on your device — you don't lose photos, messages, or settings. The update modifies the operating system files themselves, not your personal information. Most updates take 15 to 45 minutes depending on how much storage your phone has and how fast your internet connection is.
You should plug your iPhone into power before updating, because if the battery dies during installation, your phone could become unusable. After the update completes, your phone will restart and you'll see a brief setup screen, then return to your normal home screen. Some updates require you to restart your phone manually; others do it automatically. If an update fails to install, your phone usually reverts to the previous iOS version automatically.
How long your iPhone receives updates
Apple typically supports iPhones for five to six years from the year they were released. An iPhone 15 released in 2023 will likely receive updates through 2028 or 2029. An iPhone 12 from 2020 will eventually stop receiving updates, at which point you'll no longer get security patches. Once your phone stops receiving updates, it becomes increasingly risky to use for sensitive tasks like banking or shopping, because new security flaws won't be patched.
You can check how long your specific iPhone will receive updates by looking up your model on Apple's support website. The company publishes a list of which devices are compatible with each new iOS version, and when a device drops off that list, it stops receiving updates. This is one reason older iPhones eventually become less find — not because they break, but because Apple stops patching them.
What to do if an update causes problems
If your phone behaves differently after an update — an app crashes repeatedly, battery drains faster, or a feature stops working — the first step is to restart your phone. Many problems resolve after a restart. If the problem persists, check whether the app you're having trouble with has its own update available in the App Store, because app developers sometimes need to update their software to work with new iOS versions.
If a widespread problem affects many users, Apple usually releases a follow-up update within days or weeks to fix it. You can check Apple's security updates page to see what each new version addresses. If you believe you've found a genuine bug, you can report it to Apple through the Feedback app on your iPhone, though Apple doesn't respond to individual reports. For serious problems, contact Apple Support directly through their website or by visiting an Apple Store.
Preparing your iPhone before a major update
Before installing a major iOS update, back up your iPhone to iCloud or to a computer using a USB cable. This way, if something goes wrong during installation, you can restore your phone to its previous state without losing data. To back up to iCloud, go to Settings, tap your name, select iCloud, and turn on iCloud Backup. To back up to a computer, connect your iPhone with a cable, open Finder or iTunes, and select Back Up Now.
You should also make sure you have at least 5 to 10 gigabytes of free storage on your phone, because iOS needs space to read and install the update. If your storage is full, delete photos, videos, or apps you don't need, or use iCloud Photos to move your photos to cloud storage. Finally, connect to Wi-Fi and plug in your phone before starting the update, so you won't run out of battery or internet during installation.
The difference between major and minor iOS updates
A major iOS update — like iOS 17 to iOS 18 — changes the version number's first digit and usually includes new features, significant performance improvements, and sometimes changes to how your phone looks or works. These updates are released once per year and require more storage and time to install. They can occasionally cause compatibility issues with older apps, though developers usually update their apps within days to work with the new version.
A minor update — like iOS 18.0 to iOS 18.1 or iOS 18.1.1 — changes only the second or third digit and focuses on security fixes, bug fixes, and small improvements. These updates are smaller, install faster, and rarely cause problems. Apple releases minor updates throughout the year whenever security issues need patching or bugs need fixing. Both types are important for security, but minor updates are generally lower-risk to install when ready.
Frequently Asked Questions
Can I refuse to update my iPhone?
You can delay an update by dismissing the notification, but you cannot permanently refuse it. Eventually, your phone will require the update before you can use certain features or access your data. Refusing updates leaves your phone vulnerable to security flaws, so delaying is not recommended for devices you use for banking, shopping, or storing sensitive information.
Will updating my iPhone make it slower?
Most updates improve performance or keep it the same. Occasionally, a major update may run slightly slower on older iPhone models for the first few days while the system optimizes itself. If your phone feels noticeably slower after an update, restart it and check whether background app refresh is enabled in Settings. If slowness persists, contact Apple Support.
What if I don't update and my phone gets hacked?
Apple cannot remotely fix a hacked phone or recover data that was stolen before you updated. This is why updating quickly after a security update is released is your best protection. If you believe your phone has been compromised, back up your data to iCloud, update to the latest iOS, and then restore from your backup.
Do I lose my data if I update?
No. iOS updates modify the operating system but leave your photos, messages, apps, and settings untouched. Your data remains on your phone throughout the update process. However, you should still back up to iCloud or a computer before updating, in case something goes wrong during installation.
Why does Apple force updates instead of letting me choose?
Apple controls iOS updates to may support all iPhones receive security patches quickly. If updates were optional, millions of phones would remain vulnerable to known security flaws, making them targets for hackers. This approach prioritizes security over user choice, which is why Apple pushes updates to all compatible devices simultaneously.