Both phones have a slightly raised oblong Home button/fingerprint sensor in the center of the phones' front bottom edge. The Chooser and Back capacitor buttons are on the left and right, respectively, of the Home button, and light up only when they're touched. This is something of a UI problem because there's no indication that the buttons exist, let alone their function, until you use them.
Unlike the Power and Volume controls, the bottom-row controls are just OK. I've become a fan of the way LG puts a fingerprint sensor/Home button on a phone's back, and the ability in LG phones to change the arrangement of the front panel buttons to account for handed-ness. Samsung's phones always have the Chooser on the left and Back on the right.
The main camera on the back of the phones -- in the center laterally and about a half-inch from the phones' top edge -- cause a barely-there 0.5mm bump, significantly less prominent than in previous models. It's a 12MP camera that's been built with low-light shooting in mind. The camera's got an aperture of f/1.7 and fewer pixels on the same-size sensor as the S6, which lets the remaining pixels be larger. That's key for photo quality.
An LED flash and heart rate/SpO2 sensor are to the right of the camera lens. The phones have the expected complement of Bluetooth, GPS, NFC and WiFi radios. They work with Samsung Pay and Google Pay, and they still puzzle sales clerks when Samsung Pay mimics magnetic card swipes.
One of the places that Samsung has applied its processing power to is the camera. Focusing and exposure calculation is very fast. There are panorama, hyperlapse and slo-mo modes, as well as a Food mode if you're one of those annoying people who eat with their eyes. In addition, the S7s allow live streaming over YouTube. Selective focus lets you pick what part of an already-taken photo will be in focus, and there's a "virtual shot" mode that seems to be a kind of panorama mode around objects. I didn't understand it and couldn't get it to work in any interesting way.
And, for ultimate control freaks, there's Pro mode that gives you full exposure control. The camera even lets you save in RAW format.
Off to see the TouchWiz
TouchWiz is Samsung's Android UI, and it's gotten a refresh for Android 6.0. How annoying you find it will probably be a function of how much of an Android purist you are, or how much you've gotten used to other phone makers' versions of Android. As UIs go, though, there's a lot to recommend in TouchWiz.
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