The iPhone 6s has a similar design to the iPhone 6 but includes updated hardware, including a strengthened 7000 series aluminum alloy chassis and upgraded Apple A9 system-on-chip, a new 12-megapixel rear camera that can record up to 4K video at 30fps (A first in the series), can take dynamic "Live Photos", the first increase in front camera photo resolution since the 2012 iPhone 5, and also features for the first time front facing "Retina Flash" which brightens up the display three times of its highest possible brightness for selfies, 2nd generation Touch ID fingerprint recognition sensor, LTE Advanced support, and "Hey Siri" capabilities without needing to be plugged in.
[11] Before the official unveiling, several aspects of the iPhone 6s were rumored, including the base model having 16 gigabytes of storage,[12][13] the pressure-sensitive display technology known as 3D Touch,[14][15] and a new rose gold color option.
In response to the "bendgate" design flaws of the previous model, changes were made to improve the durability of the chassis: the 6s was constructed from a stronger, 7000 series aluminum alloy,[24] "key points" in the rear casing were strengthened and reinforced, and touchscreen integrated circuits were re-located to the display assembly.
[28][29] Although the device was not promoted as such, the iPhone 6s has a degree of water resistance because of a change to its internal design, which places a silicone seal around components of the logic board and an adhesive gasket around the display assembly[30] to prevent them from being shorted by accidental exposure to water.
The iPhone 6s features a technology known as 3D Touch; sensors are embedded in the screen's backlight layer that measure the firmness of the user's touch input by the distance between it and the cover glass, allowing the device to distinguish between normal and more forceful presses.
The 16 gigabyte version of the phone was only capable of holding 40 minutes of 4K video (bit rate: 6 MB/s or 48 Mbit/s).
[45] For improved storage performance, iPhone 6s utilizes NVM Express (NVMe), resulting in a maximum average read speed of 1,840 megabytes per second.
[47] The iPhone 6s originally shipped with iOS 9; the operating system leverages the 3D Touch hardware to allow recognition of new gestures and commands, including "peeking" at content with a light touch and "popping" it into view by pressing harder,[32] and accessing context menus with links to commonly used functions within apps with harder presses on home screen icons.
The battery life was criticized, and one reviewer asserted that the phone's camera was not significantly better than the rest of the industry.
However, Apple saw its first-ever quarterly year-over-year decline in iPhone sales in the months after the launch, credited to a saturated smartphone market in Apple's biggest countries and a lack of iPhone purchases in developing countries.
There just aren't other companies that can roll out a feature like 3D Touch and make it work in a way that suggests the creation of entirely new interface paradigms, and every other phone maker needs to figure out exactly why Apple's cameras are so consistent before they can really compete.
"[49] Samuel Gibbs of The Guardian commented that the phone "has the potential to be the best smaller smartphone on the market, but its short battery life is deeply frustrating" and described the camera as "not leagues ahead of the competition anymore".
[53][54][55] In the months following the launch, Apple saw its first-ever quarterly year-over-year decline in iPhone sales,[56][57] attributed to a saturated smartphone market in Apple's biggest sales countries and consumers in developing countries not buying iPhones.