Most smartwatches on the market today act as companions for your mobile devices, letting you view your smartphone's notifications or app content on your wrist. Exetech's XS-3 packs Android 4.0 and a SIM slot so it can work without a linked smartphone, and joins the likes of the Neptune Pine, the Goophone watch and the Watchphone as an independent wrist-worn computer. You can get the XS-3 in Black (White available in the future) for $480 (349 EUR) on Exetech's website.

Measuring 2.54 x 1.73 x 0.69 inches and 2.32 ounces, the XS-3 is the sleek cousin of the bulky Neptune Pine. It packs a smaller 1.54-inch 240 x 240-pixel face compared to the Pine's 2.5-inch 320 x 240-pixel display. With a dual-core MediaTek MTK 6577 CPU though, the Exetech may offer better performance than the Pine, which sports a single-core processor.

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The Exetech XS-3 carries a replaceable 420-mAh battery that can last some 18 hours on standby, according to Engadget, and about 7 hours on heavy use. Onboard, the XS-3 also offers a 2-MP camera on its right side, a microSD card slot for up to 32GB of expandable storage and a microUSB port for charging and connecting headphones (with an adapter). It also supports Bluetooth (though Exetech doesn't specify which type), Wi-Fi, GPS and is compliant with IP65 standards for water and dust resistance.

In comparison, the Neptune Pine packs a 5-MP camera on its rear and a VGA camera up front, along with a microUSB slot. You can also slide off the Pine's watch face to quickly snap pictures. The Android 4.0.4 OS on the Exetech is primitive compared to the Neptune Pine's 4.2 Jelly Bean.

While both the XS-3 and the Neptune Pine are much chunkier than competing products such as the Galaxy Gear 2 and the Pebble Steel, they offer more functionality with access to the Google Play store for apps. Both also offer SIM card slots and 3G radios for freedom from linked devices. With that functionality and pricing, the XS-3 could be the only mobile device you carry.

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