"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
iPhone 6s Plus Touch ID Much Quicker Than iPhone 6 Plus in New Hands-On Video
The 6s Plus' Touch ID unlocks the phone almost instantaneously, taking a user straight to their Home Screen when they rest their finger on it. Comparatively, the speed of the 6 Plus' Touch ID makes it seem like a two-step feature, first waking up the display and then taking a user to the Home Screen.
On first impression, some users think the new Touch ID is too fast, however. Reddit user MasterofLuiz notes that it's so fast it affects how he usually uses his phone.
I can't even click the home button to check the clock without it automatically unlocking the phone. It's crazyMacRumors forum member mykaluk has attempted to best the speed of the new Touch ID, attempting to tap the Home Button so quickly that it doesn't read his fingerprint. However, he notes that the Touch ID is able to read the fingerprint every time.
Be sure to check out the iPhone forum to join the discussion about the two new phones and their new features, or visit the iPhone accessories forum to see how the new cases look on the new devices, or whether existing cases fit the new devices. If you'd like to find out which apps take advantage of 3D Touch, make sure to check out the iOS Apps forum.