Apple unveiled its second generation smartwatch today at its annual mobile hardware event, and it is unsurprisingly called the Apple Watch Series 2. The device is very similar to its predecessor: it's got a square, customizable watchface mostly for telling the time and displaying notifications; a single-day battery life; and a funky watch dial Apple calls the digital crown for scrolling and zooming. The biggest changes, however, are a new water-resistant shell, which makes the watch swimproof, and the addition of a GPS chip.

The built-in GPS allows the device to perform mapping on its own, no phone required. According to reports last month, Apple decided not to include cellular connectivity, likely out of concern for the device's already strained battery. So while the new Apple Watch can tell you where to go when you're out for a run, it cannot receive app notifications, make calls, or send texts.

The company also upgraded the processor in the device, now called the S2, and the display. The Series 2 has a dual-core processor Apple says is 50 percent faster than its predecessor, with double the graphics performance thanks to a new GPU. The display is now 50 percent brighter as well. So now, using apps and general maneuvering through the watch's interface is much snappier, especially with the software-side upgrades we're getting with watchOS 3.

Apple Watch Series 2 is swimproof with a new processor, brighter display, and GPS chip

The Apple Watch Series 2 retains the same casing for the lower- and middle-tier versions. So the cheapest version comes with an aluminum case, while the next tier up has a stainless steel one. This time around, however, Apple is adding a white-colored ceramic model for luxury customers who want to drop thousands on the smartwatch. There's no word yet on the future of the gold Apple Watch Edition.

The company has also renewed its longstanding partnership with Nike with a special Nike+ version of the Apple Watch. It resembles a fusion of an Apple product with Nike's discontinued FuelBand fitness tracker, and it's designed for runners and workout junkies.

The aluminum sport version of the Apple Watch Series 2 will start at $369, as will the Nike+ edition. The original Apple Watch is being rebranded as Series 1 and will start at $269, though it will come with the upgraded S2 dual-core processor. Preorders start on September 9th, while the watchOS 3 update will go live on September 13th. The sport and stainless steel versions start shipping the week after watchOS 3. Apple Watch Nike+ will be available in late October, the company says.

Since launch, Apple's smartwatch has become the best-selling device in its category, though smartwatches still trail far behind the more basic fitness trackers that companies like Fitbit excel at. Yet when speaking about the Apple Watch in comparison with other big-name brands, Apple CEO Tim Cook said today the product line became the No. 2 watch line by revenue just 18 months after launch, behind only Rolex products.

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