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, 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.