The iPhone is hybrid between the iPhone 5S and 6S. You have the form factor of the 5S with a four-inch display and the fact that you can easily use the phone with only one hand, combined with the agility of the performance of the 6S. The camera is also one of the best that you can get your hands on a 12-megapixel sensor that also takes 4K video. These combine to create a compact and capable device that is also the cheapest iPhone ever.
Source: t3.com Image: cnet.com