Update and restore software on iPod, iPhone, or iPad
Using iTunes, you can update software on your iPod, or update iOS software on iPod touch, iPhone, or iPad.
If you are having problems with your device, you can also use iTunes to reinstall the software and restore your device’s default settings.
Important: Restoring iOS software on iPod touch, iPhone, or iPad deletes your information, but doesn’t erase it. Deleted information can’t be accessed through the device’s controls, but it remains on your device. To find out more about erasing all content and settings (if, for example, you plan to give your iPhone away), see this article at the Apple Support website.
Update or restore your software
Connect your iPod, iPhone, or iPad to your computer and select your device.
Click the Summary button.
Do one of the following:
See if a newer version of the software is available: Click Check for Update.
Restore your software: Click Restore, and follow the onscreen instructions.
To install an available update, click Update.
If you’re restoring software on your iPod touch, iPhone, or iPad, iTunes backs up your device at the start of the process. You can restore your settings from the backup at the end of the restore.