Working to expand its Gear smartwatch lineup to as many different models and styles as possible, Samsung announced the Gear S in August 2014 with a few interesting features to set it apart from the rest of the Gear lineup. First off it has a quite large 2-inch AMOLED display that's curved to better fit the wrist, and second it has stand-alone 2G and 3G connectivity, as well as Wifi, for full functionality when not connected to a phone over Bluetooth.
Though Android Wear was readily available at the time of launch — and used on Samsung's Gear Live watch — the Gear S runs Tizen like its other latest Gear devices. That means a familiar interface if you've used anything going back to the original Galaxy Gear (which since launch switched to Tizen for its OS), including a full suite of modern smartwatch features. You can even call and send messages via the watch independently of your phone (after the initial setup), if you wish.
As for specs, the Gear S has a pretty basic set of internals for a computer that's strapped to your wrist. A 1GHz dual-core processor, 512MB of RAM and 4GB of RAM run things, while a 300mAh battery purports two days of "typical usage." On the underside of the band you'll find a heart rate sensor, building into Samsung's S Health platform, paired with IP67 water and dust resistance for when you're exercising.