I have an older IPhone with IOS 4.2.1 and was wondering if it's possible to update any further or at least to 4.3?
The 3G cannot be updated beyond 4.2.1. The 3GS can be updated to 5.1.1. To see which you have enter its serial number here.
Yes, an iPhone 3GS can be upgraded to iOS 4.3 and also 5.1.1. However, if iTunes is telling you that the phone is up to date at 4.2.1, it may mean that you actually have an iPhone 3G, not a 3GS.
Thanks Stedman, appreciate the reply. Finally figured out that I actually have the 3G rather than the GS model.
You're welcome, and thanks for marking the question as solved.
stedman1 do you mean iphone (3G) can not be upgraded?
Correct, the iPhone 3G can not be upgraded beyond iOS 4.2.1.
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