iPhone 6s and iPhone 6s Plus are a worthy continuation of the iPhone series. There are almost no external differences with its predecessors (6 and 6+), but the differences affected the hardware component. The processor was replaced by Apple A9, which gave the smartphone more performance. The amount of RAM has also increased to 2 GB. The screen was improved with 3D Touch technology, which allowed it to become sensitive to pressure. An improved Touch ID 2 fingerprint scanner was installed in the 'Home' button, which allows for almost instant authorization on the device. The main camera has an extension of 12 MP with the ability to shoot 4K video with a frame rate of 30 fps. The front camera received an extension of 5 MP. The iPhone 6s model took first place in terms of shipment volumes in 2016. This smartphone remains relevant to this day and is actively sold on the 'secondary market'.