iOS updates bring new features, security fixes, and sometimes new bugs. Updating safely takes 30 minutes if everything goes smoothly. Here's how to do it without losing data or breaking your apps.
Major updates (iOS 17 to 18) are different from minor ones (17.4 to 17.5). I'll cover both.
Back up first
Always. iCloud backup is the easiest method. Settings > your name > iCloud > iCloud Backup > Back Up Now.
If iCloud storage is full, free space or back up to your computer instead. Connect iPhone to Mac (Finder) or PC (iTunes). Pick your iPhone, click Back Up Now.
Computer backups don't use iCloud space and include encrypted health and keychain data if you check the option.
Plug in and connect to Wi-Fi
Charge the iPhone above 50% before starting. Better – leave it plugged in during the entire update. Updates can take 30-60 minutes and the phone uses significant power.
Connect to Wi-Fi too. iOS updates are big (3-5 GB usually). Cellular data downloads are slower and can hit your data cap quickly.
Check storage space
iOS needs free space for the update plus temporary working space. Usually 5-10 GB minimum. Settings > General > iPhone Storage shows your current usage.
If you're tight on space, iOS suggests files to remove. Offloading unused apps is the quickest way to gain space without losing data.
Run the update
Go to Settings > General > Software Update. iOS checks for available updates. If one shows, tap Download and Install.
Agree to terms. Enter your passcode. The download starts. When complete, the install begins automatically or asks if you want to install now or later.
During the install, the screen shows an Apple logo and progress bar. Don't use the phone. Don't unplug. Wait until you see the Hello screen or your normal lock screen.
Major update vs minor update
| Type | Typical size | Time |
|---|---|---|
| Minor (e.g. 17.4 to 17.5) | 500 MB – 1 GB | 15-20 min |
| Major (e.g. 17 to 18) | 4-7 GB | 45-90 min |
| Security update only | 200-400 MB | 10 min |
Major updates take longer and risk more issues. Don't install on the first day of release if your phone is critical. Wait 1-2 weeks for early bug reports.
Should you skip a beta iOS?
Apple offers a Developer Beta and a Public Beta program. Beta iOS gives early access to new features but is buggy. If your iPhone is your only phone, skip beta.
Beta updates can break apps, drain battery faster, and have stability issues. Useful for testing but not for daily reliable use.
After the update
The phone boots up. Sign in. iOS does post-install setup like syncing iCloud, indexing search, checking apps.
The first hour after a major update, the phone might feel slow. Don't panic. Background indexing is happening. Performance returns once that finishes.
Battery often drains faster too in the first 24-48 hours. Same reason – background tasks catching up. Wait it out.
Common post-update issues
Things that sometimes break after iOS updates:
- Apps need to be opened once to refresh their permissions
- Some apps haven't updated for the new iOS and crash on launch
- Wi-Fi might disconnect once – reconnect manually
- Bluetooth pairings might need re-doing
- Battery life suffers for 1-2 days before stabilizing
Most issues clear up in 24-48 hours. If something stays broken longer, search the iOS version + your issue. Apple usually patches major bugs in point updates within weeks.
Roll back if disaster strikes
If a new iOS truly ruins your phone, you can sometimes downgrade. Apple stops signing old iOS versions a few weeks after a new release. Within that window, you can roll back via iTunes or Finder.
Connect to a Mac or PC. Put iPhone in recovery mode. Download the older IPSW from ipsw.me (only if Apple still signs it). Restore.
This wipes your phone so backup first. Restoring from backup after downgrade can be tricky if the backup is from the newer iOS.
Don't skip security updates
Even if you stay on an older iOS major version, install security patches. Apple releases these for older versions too.
Settings > General > Software Update. If a security-only update is available, it shows separately. Install it. Doesn't change features, just patches vulnerabilities.
Which iOS version are you on currently? Tell me and I'll point to whether updating is worth it now or worth waiting.