iPhone 12 Lagging or Running Slow? Here’s How to Fix It

If your iPhone 12 suddenly starts lagging, freezing, or just feels slower than usual, you’re not alone. These performance issues usually come from software glitches, app overload, or cluttered settings. The good news? You can often fix the sluggish behavior with a few simple steps — no Genius Bar visit required.

Here’s how to get your iPhone 12 running smoothly again.

Close All Background Apps

Apps running in the background still use your phone’s RAM and processing power — especially games or resource-heavy apps that don’t pause properly.

Swipe up from the bottom of the screen and pause in the middle.
Swipe up on each app preview to close it.

Once you’ve cleared them all, use your iPhone normally and see if it’s still lagging.

Force Restart Your iPhone

A quick force restart helps refresh system memory and reload background processes that might be dragging things down.

Press and quickly release the Volume Up button.
Press and quickly release the Volume Down button.
Press and hold the Side button until you see the Apple logo.

Let your iPhone finish booting, then check for improvements.

Reset All Settings

If the lag started after a recent settings change or update, resetting all settings can help — without deleting your personal data.

Open Settings > General > Transfer or Reset iPhone.
Tap Reset > Reset All Settings.
Enter your passcode if asked, and confirm.

Your Wi-Fi networks, preferences, and system settings will be reset, but your apps and files stay untouched.

Update iOS

Apple often includes performance tweaks and bug fixes in iOS updates.

Go to Settings > General > Software Update.
Download and install the latest version if one is available.

This is especially helpful if the lag began after a major iOS upgrade.

Free Up Storage Space

If your storage is nearly full, your iPhone can slow down significantly.

Go to Settings > General > iPhone Storage.
Delete unused apps, old photos, or large files you no longer need.
Offload unused apps to save space without deleting their data.

Aim to keep at least 5–10 GB of free space if possible.

Factory Reset Your iPhone (As a Last Resort)

If nothing else works, a full reset can help eliminate deep software issues. Make sure to back up your data before doing this.

To reset:

Go to Settings > General > Transfer or Reset iPhone.
Tap Erase All Content and Settings.
Enter your passcode and Apple ID password if prompted.
Confirm to begin the reset.

Once the reset is done, set up your iPhone as new (avoid restoring from backup at first — test for lag issues).

Still Lagging? Contact Apple Support

If you’ve tried all of these and your iPhone 12 is still slow, you might be looking at a hardware issue — possibly with the storage, processor, or battery health. You can check your battery’s condition under Settings > Battery > Battery Health & Charging.

If needed, book a Genius Bar appointment or start a chat with Apple Support online.