iPhone not working after update? Fixes for every common problem

What is normal for the first two days

• Faster battery drain and a warm phone while it re-indexes.
• Slight lag in Photos and search.
• Apps asking you to sign in again.

If your iPhone has been strange since the update, you are not alone, and it is rarely permanent. The days after a major iOS release always bring a predictable set of complaints: battery drain, heat, lag and a few apps that misbehave. Most settle by themselves within a couple of days, and Apple usually ships a bug fix within a few weeks for anything that does not. Knowing which is which saves you from drastic steps, like erasing the phone, that rarely help. To see which version is current and what each update fixed, check our iOS and Android updates tracker. Below are the general fixes, then specific steps for each common problem.

How to fix iPhone not working after update

A realistic timeline

• Day 1 to 2: indexing, warmth and battery drain are normal. Charge overnight on Wi-Fi.
• Week 1: app developers release updates for the new iOS. Keep App Store updates on.
• Weeks 2 to 4: Apple usually releases the first bug-fix version, which fixes the most widespread problems.
• After a month: anything still wrong is worth a reset of settings or a call to Apple Support.

Face ID or Touch ID stopped working

After an update, iOS always asks for your passcode once before Face ID or Touch ID works again, which is normal. If Face ID keeps failing after that, restart the iPhone, clean the TrueDepth camera area at the top of the screen, and check Settings › Face ID & Passcode. As a last step, tap Reset Face ID and set it up again. If you see a message that Face ID is not available, see what to do when Face ID is not working.

Apple Watch acting up after the iPhone update

A new iOS often comes with a matching watchOS update. Open the Watch app on the iPhone, go to General › Software Update and install it, with the watch on its charger. Until both are updated, notifications, health sync and unlocking with the watch can be unreliable. Restart both devices after updating, then test again.

Fixes by problem

• Battery draining fast: wait two days, then check Settings › Battery for an app using far more than usual and update or remove it. See why an iPhone battery drains fast.
• Hot iPhone: normal during indexing. If it is still hot after two days while idle, look for a runaway app in Battery settings and restart.
• Slow or laggy: free some storage, restart, and give indexing time. If it is still slow after a week, see how to speed up a slow iPhone.
• One app crashing: update it; if no update exists yet, offload and reinstall it, or wait for the developer’s fix.
• Many apps crashing: restart, then check for a small iOS update, which often fixes these bugs.
• Wi-Fi or Bluetooth problems: forget the network or device and reconnect, then reset network settings if needed.
• No service or SOS: install the carrier settings update, toggle Airplane Mode and restart.
• CarPlay not connecting: forget the car in Settings › General › CarPlay, restart the iPhone and reconnect with a good cable.
• No sound or quiet calls: check the volume, Silent mode and Focus, which updates sometimes change.
• Keyboard lag: reset the keyboard dictionary in Settings › General › Transfer or Reset iPhone › Reset.
• Missing notifications: review Settings › Notifications and your Focus modes, since new options may be on by default.

Photos, messages or widgets look different

Big updates often redesign apps such as Photos, Messages and the Phone app, and some layouts are optional. Before assuming something is broken, look for a layout or view option in that app, for example the Phone app’s classic and unified layouts in iOS 26 and later. Photos may show items as still processing for a while after the update, and widgets can return to their default size; edit the Home Screen to set them back.

Stuck on the Apple logo or restarting

If the iPhone never finishes starting after the update, or restarts again and again, connect it to a computer, put it in recovery mode and choose Update first, which reinstalls iOS while keeping your data. Only choose Restore if Update fails, since it erases the phone. See how to fix an iPhone stuck on the Apple logo and why an iPhone keeps restarting.

Work, school and banking apps

Apps managed by an employer or school, and some banking and health apps, can take longer to support a new iOS, and a few refuse to open until they are updated. If a must-have app stops working, check the App Store for an update, look at the developer’s website or social accounts for a known issue, and use the website version in the meantime. For work phones, ask your IT team before updating next time; many organizations hold back major updates for a few weeks for this reason.

Should you reset or restore?

Reset All Settings keeps your data and fixes many lingering problems caused by settings that did not carry over cleanly, so it is worth trying before anything bigger. Erasing the iPhone and restoring a backup is rarely needed for update problems and can bring the same issue back, since the backup includes your settings. Only erase if Apple Support recommends it, and make a fresh backup first. See making an iPhone backup.

Is it the update or the hardware?

Sometimes a problem appears around the time of an update by coincidence. A worn battery is the most common example: a new iOS asks a little more of it, and an old battery that was barely coping starts shutting down. Check Settings › Battery › Battery Health & Charging to see where your battery stands. If Maximum Capacity is low or there is a service message, a battery replacement, not a software fix, is the answer. Problems that started after a drop or water exposure are hardware too.

Avoid the same trouble next time

• Back up right before every major update, every time, so a bad install never costs you data.
• Keep a few gigabytes of storage free; a nearly full iPhone is more likely to have problems after updating.
• For big yearly releases, waiting a week or two for the first fix is reasonable if your phone works well today.
• Keep apps updating automatically, so they are ready when the new iOS version arrives.

Tell Apple about the bug

If you have found a real bug, report it. Contact Apple Support through the Apple Support app or getsupport.apple.com and describe exactly what happens, when, and on which iPhone model. Bugs that many people report are usually the ones fixed first in the next update, so your report genuinely helps. Meanwhile, check apple.com/support/systemstatus if the problem involves iCloud, iMessage or the App Store, since those can be server-side issues rather than your phone.