The iPhone 6S is equipped for the first time with a new display that has integrated the "Force Touch" technology. With Force Touch, also called "3D touch" on the iPhone 6S you can perform different functions by different strong pressure on the display.
If that's too much gimmick on your new iPhone 6S is, you can of course disable 3D Touch in the settings of iOS. Where you can find the setting exactly we tell you now precisely in this article:
Open from the home screen of your iPhone 6S the settings. Then from here navigate to:
General --> Accessibility
Tap now on "3D touch" to enter the submenu. Then you can disable on the top with the regulator 3D Touch on your iPhone 6S completely. You now know where 3D Touch on the iPhone 6S can be turned off.