This cousin of the S9 has a larger screen, larger battery, and an extra camera with a telephoto lens. Compared to last year's S8+, the fingerprint reader has been moved and the camera can adjust aperture for low light. Other key features a top-end processor, quad-HD+ display, water resistance, iris scanner, Samsung Pay, support for Samsung's DeX desktop dock, fast wireless charging, memory cards, and 3.5mm headphones.