One of the problems with using an Android Wear smartwatch is that you have to be tethered to a smartphone to get the most out of it. That isn't the case with the LG Watch Urbane Second Edition. LG's new smartwatch is the first Android Wear watch to feature cellular connectivity, meaning you can make calls and receive notifications even when your leave your iPhone or Android device behind.

(The Android Wear distinction is important: Samsung's 2014 Gear S and 2015 Gear S2 smartwatches offer on-board cell connections, but those are powered by Samsung's proprietary Tizen operating system, not Google's Android Wear.)

The new Urbane -- a followup to LG's earlier Urbane model that debuted in May -- features some of the most impressive hardware we've seen in an Android Wear watch, at least on paper. The watch includes 2G, 3G and 4G LTE radios, along with GPS, Bluetooth and Wi-Fi. For US customers, the watch will be available at AT&T on April 1 for $360. Verizon users can get it for $450 if they sign up for a two-year contract or $500 without.

All of these connectivity capabilities are built directly into the band. Unfortunately, that means you won't be able to swap out the strap for a new one like you can with other Android Wear watches. LG is offering the watch with a rubber band in either brown, black, white or blue.

Editors' note: This piece has been updated on March 24, 2016 to include US carrier news.

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The 1.3-inch display is fully round, is made of LG's new Plastic OLED material and has a 480x480-pixel resolution. That works out to 348 pixels per inch and is the highest resolution of any Android Wear watch to date, surpassing the 400x400 display of the Huawei Watch . LG was showing off a prototype that wasn't powered on, so we couldn't judge how sharp the display looked. As for size, it only comes in one -- 44.5mm.

The watch is designed with 316L stainless steel, but it looks more like a sport watch than the original Urbane. It's also considerably thicker than the original model. The included cellular capabilities are a welcomed addition to Android Wear, but you will need a separate phone number and data plan to use the watch, unless you swap your SIM card from one device to the other. Calls are made with a built-in speakerphone, which was surprisingly loud even in a crowded conference hall.

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On the inside, the watch is just like every other Android Wear watch. It's powered by a 1.2GHz quad-core Snapdragon 400 processor and features 4GB of space to store music and apps. LG bumped up the RAM (which is usually 512MB) to 768MB and included a large 570mAh battery, which also happens to be the world's first hexagon-shaped battery. But despite that large size, you will most likely have to charge the watch every night. The new Urbane is estimated to only last around a day and a half to two days, depending on usage.

Charging is done the same way as LG's other Android Wear devices. Four pins on the back of the watch are connected to a special dock. The new Urbane boasts an IP67 rating, which means it can withstand splashing and showering, but it's not recommended for swimming. This is true for all Android Wear watches.

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The watch has three buttons: a shortcut to favorite contacts, a crown to dim the display and another button to quickly open LG's Health app. On the back, there's also a heart-rate sensor. LG noted how the new Urbane features "stress level monitoring" and "personal coaching" for workouts, but it remains unclear how these actually function.