by darkthorn » 03 Sep 2015, 18:21
Not that I know. Have you tried to connect your device to your computer and open iTunes in order to upgrade?
Bellow there is an upgradability and 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
-------------------------------------------------------
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
-------------------------------------------------------
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
=====================================
If there is no more update option with iTunes that is probably because the device does not have the ram and processor speed to run a more recent version of the operating system. The solution is to buy a new device or just keep using that one as long as it does what you need. If there is other options I really don't know

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