Behind every great design, in any industry, is a story, and the Samsung Galaxy S8 is no different. Samsung took to their newsroom to spread that particular story, and said right off the bat that one of the biggest things was to make the whole experience, from the inside out, holistic and organic, getting rid of or reworking anything that seemed "needlessly mechanical". With beautiful nature wallpapers accenting the different color options and "glass flowing like streams of water", the natural inspiration here is plain to see, and the feeling that the Galaxy S8 gives is not entirely dissimilar to that of the Galaxy S3, Samsung's first Android flagship that took cues from nature.
On the hardware end of things, looking natural is only a small part of the equation. The biggest element of the design is the subtle curve on both sides of the device, meant to fit perfectly in the hand without requiring any hand gymnastics or feeling unnatural. The color options were chosen to highlight and complement natural colors that users would invariably encounter in everyday life, making all of the options more appealing because they're made to match their environment, and not just their user's hair, eyes, or outfit. Lower intensity and saturation in the colors chosen helps to keep the phone from looking garish or sticking out. Even Samsung's first-party cases are made to look and feel natural and luxurious by clinging to the same design conventions as the phone.
The obsession with a natural and holistic feeling extends to the user interface. Round icons, more naturally flowing menus, UI design elements meant to feel intuitive, and full integration with the Galaxy S8's large, flowing screen are all here to make for a more harmonious experience. Samsung calls the subtle continuity found in most of the software elements the "ambient visual effects of a galaxy". This language is not actually too far off; not unlike the swirling galaxies in the heavens, everything here flows into the next element to foster the creation of patterns and continuity; the Always On Display feature blends nicely into the lockscreen, which itself transitions seamlessly and subtly to the home screen, which blends nicely over to the app drawer or the settings menu. A number of new elements on the homescreen, like new icons and widgets, have been made to blend together and feel more natural and cohesive. Transition animations ensure that even apps that don't play nice with Samsung's design philosophies don't make the experience feel incoherent. Bixby, Samsung's answer to Siri and Google Assistant, completes the puzzle by understanding natural speech and serving up situationally relevant information or insight on the user's surroundings through various features like Bixby Vision, which all integrate seamlessly into the rest of the UI design.