iPhone 6S will be stronger
https://gadgetexperiance.blogspot.com/2015/08/iphone-6s-will-be-stronger.html
GadgetXp - The new generation iPhone soon believed to be immediately released. Apple certainly has made a number of improvements. One of them is by strengthening the resilience of the body so that it cannot easily bent.
A number of rumors mentioned that Apple would use the 7000 grade aluminium. This material was previously used to make Apple body Watch, which offers a much better durability than that used on the iPhone 4.
This has been evidenced by the Unbox Therapy. As reported by the Pocket Now, Friday (20/8/2015), they managed to get a glimpse of the latest generation iPhone body frame. Then compare with the iPhone 6 by doing testing in the form of the test pressure.
In initial testing, Unbox Therapy using weights weighing 30 pounds or about 13 kg. In a short time, bodi 6 iPhone directly. While iPhone 6S can still survive.
It was only after being given a burden 80 pounds or about 36 kg, bodi iPhone 6S so crooked. This means that iPhone 6S have trebled durability compared to previous generations. This result will be increased when the iPhone has assembled intact.
To see clearly the test process, the following video: