Agree with this 100%, i don't think Apple are going to do anything radical to change the iPhone, after all it sells and it sells VERY well indeed. I don't know what people expect but i have a hard time seeing how the iPhone will change much in terms of design, there isn't really much that can be done with it in terms of it's shape. This doesn't really bother me anyway, i have the iPhone 6 Plus and i think it's great.
Sometimes people expect too much, for example some people were saying that the iPhone 6S isn't a massive leap, but the 3D feature and live photo's are great, i feel that they change the way people use the phone, my best friend has the 6S and I've played with the 3D touch feature, it's a great addition, so is the live photo's, my best friend has a young child and the live photo really is useful for capturing great moments, for example at her sons 9th birthday party.
I personally don't think the iPhone needs drastic or massive design changes, sometimes subtle features such as 3D Touch and Live photo's add more to it than anything else.
(sorry for the long really

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