iPhone 3GS and iPhone 4 Can't Support All Features Offered in IOS 6

As already known, the iPad first generation and third-generation iPod touch will not get the update IOS 6, but in spite of the update to IOS-6, not all devices will have all the features offered in IOS 6. Carrying only the A5 processor or A5X ( iPhone 4S, iPad 2, and the new iPad) that can use the navigation features Flyover and turn-by-turn in the IOS 6.  Apple does not give a reason why they set this thing, so the conclusion while this feature is absent because the processor is considered old. iPhone 4 also listed can not do FaceTime feature over a cellular network. IOS-6 in the iPhone 3GS will also miss a few more features such as shared photo streams, and email features VIP flag, and offline reading. Recalling the iPhone 3GS was three years old, so understandably some features not provided by Apple in order to maintain performance.
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