A (3D) TOUCH ABOVE
Apple iPhone 6s and 6s Plus
internals. We saw this when Apple launched Siri with the 4s, Touch ID with the 5s, and now 3D Touch with the 6s. This cycle of upgrades allows Apple to focus on updating one half of the iPhone at a time, essentially giving the internal and external teams two years each to develop and perfect their next generation technologies.
Look at the specs and you'll see that the new iPhones aren't actually completely identical to their predecessors. Both the iPhone 6s and 6s Plus are fractions of a millimeter wider, longer, and thicker than their iPhone 6 equivalents. Having said that, you won't be able to tell the difference, and if you have a case made for the 6 or 6 Plus, it will fit the 6s and 6s Plus just fine.
What is noticeable is the change in weight. Both of the new iPhones are heavier than last year's models - due to the new 3D Touch sensors and the haptic feedback engine under the display - and while it's only 14g more for the 6s and 20g for the 6s Plus, you can definitely tell. Don't get me wrong, these aren't heavy phones by any measure, but the weight is perceptible in a way the added dimensions aren't.
The new iPhones are made from a stronger 7000-series aluminum - the same material Apple uses on the Apple Watch Sport. The new aluminum is tougher than last year, which should avoid a repeat of #bendgate, but is otherwise indistinguishable. The front of the phone is tougher too. The new glass covering the screen uses a dual-ion exchange process that makes it less prone to shattering if you drop it and it's also more resistant to scratches.
Below the screen, the new iPhones are fitted with a second-generation Touch ID fingerprint scanner that is insanely fast. In fact, it's so fast