So what will change?
If the design of the iPhone 6S remains the same, then Apple will provide upgrades in the form of new hardware. There are various rumours floating around, the most obvious of which, is of a new processor. The iPhone 6S will come with an A9 chip and could also get an upgrade in the RAM department to 2 GB.
The Touch ID fingerprint scanner could be integrated into the display, according to one rumour, rather than sitting in the home button. Cameras will almost certainly be upgraded although we're not sure a rumoured 21 Mp rear camera is probable.
More likely is a reversibly USB connector. We already have the Lightning connector which can be plugged in either way round so we'd put money on Apple doing it at the other end of the cable, too. Also highly possible, practically a given, is that the iPhone 6S will come pre-loaded with iOS 9 which will probably be detailed at Apple's WWDC which normally takes place in June.
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