MY PHONE IS 4.2.1 I WANT TO UPDATE 6.
my phone is 4,2,1 i wnt to downlode viber and whatsup . i get massage to up date 6
iPhone 4, iOS 6.1.5
Update it from iTunes on a computer as described at the bottom of this article; devices running an iOS version prior to 5.0 can't be updated straight from the device. It will be updated to the newest iOS release supported by the device’s hardware, which is iOS 7.1 for devices with at least 512MB of RAM.
The maximum iOS version for the second generation iPod touch and the iPhone 3G is 4.2.1.
The maximum iOS version for the fourth generation iPod touch and iPhone 3GS is 6.1.6.
If you don't know what device you have, append the last three characters of its serial number to http://www.everymac.com/ultimate-mac-lookup/?search_keywords= and load the page.
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