Connect to computer and open iTunes.
See the chart below to determine whether you can upgrade your device and what you can upgrade to.
IPhone, iPod Touch, and iPad iOS Compatibility Chart
Device iOS Verson
iPhone 1 iOS 3.1.3
iPhone 3G iOS 4.2.1
iPhone 3GS iOS 6.1.x
iPhone 4 iOS 6.1.x
iPhone 4S iOS 6.1.x
iPhone 5 iOS 6.1.x
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iPod Touch 1 iOS 3.1.3
iPod Touch 2 iOS 4.2.1
iPod Touch 3 iOS 5.1.1
iPod Touch 4 iOS 6.1.x
iPod Touch 5 iOS 6.1.x
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iPad 1 iOS 5.1.1
iPad 2 iOS 6.1.x
iPad 3 iOS 6.1.x
iPad 4 iOS 6.1.x
iPad Mini iOS 6.1.x
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Select the method most appropriate for your situation.
Upgrading iOS
1. How to update your iPhone, iPad, or iPod Touch
2. iPhone Support
3. iPod Touch Support
4. iPad Support
a. Updating Your iOS to Version 6.0.x from iOS 5
Tap Settings > General > Software Update
If an update is available there will be an active Update button. If you are current,
then you will see a gray screen with a message saying your are up to date.
b. If you are still using iOS 4 — Updating your device to iOS 5 or later.
c. Resolving update problems
1. iOS - Unable to update or restore
2. iOS- Resolving update and restore alert messages