Well this is something most of us would not expect from Apple. The next-generation iPhone - the iPhone 6S is going to be slightly thicker because Apple is going to incorporate Force Touch technology and maybe a better battery - which I know most of you will be welcoming with open hands.
A new report today from KGI analyst Ming-Chi Kuo, who has a good track record when it comes to Apple, mentioned that Apple is going to slightly increase the thickness of the iPhone 6S by 0.12 mm and 0.15mm in length; although this might not seem a lot but this slight increase in sizes is going to make an impact that will be noticeable.
There are many reasons for increasing the size, the first and the most important being that Force Touch technology, which is the feature that will make the screen more clickable, needs a new layer, so increasing the thickness makes more sense. Also currently the camera slightly protrudes, which makes the iPhone a bit shaky when you place it on a surface; increase the size will make it more even.
The camera on the iPhone 6S is going to get an upgrade, from the current eight megapixel to 12 megapixel. Which is going to be nice, since the last time we got a major camera upgrade was for the iPhone 4S.
Also the iPhone 6S is going to get a stronger aluminum, which will remove the BendGate problems many had been facing, especially for the iPhone 6 Plus owners