Having already launched in many world markets, Samsung has now unveiled the Samsung Galaxy S II models that are destined for U.S. carriers from September. The company's flagship smartphone will come in three slightly different flavors through Sprint, AT&T and T-Mobile, with all running Android 2.3 (Gingerbread) with Samsung's TouchWiz 4.0 UI and packing a 1.2 GHz dual-core processor, 1GB of RAM, and Super AMOLED Plus touch screen display in a slim form factor. Although Samsung has revealed an LTE version is on the way, the three phones initially on offer will use HSPA+ (AT&T and T-Mobile) and WiMAX (Sprint) for 4G connectivity.

All variants feature a 2-megapixel front-facing camera for video chat, and an 8-megapixel rear-facing camera with autofocus and flash that can record 1080p video. There's also Bluetooth 3.0, Wi-Fi 802.11 b/g/n/a, 16 GB of on-board memory and a microSD slot supporting cards up to 32 GB. Six-axis motion sensing is possible thanks to an accelerometer and gyroscope, while a Voice Talk feature lets users dial, test message, navigate, browse the Web, search and select music using voice commands. With multi-tasking in mind, the Task Manager also lets users view and close active applications, check what items have been downloaded, and check on memory usage.

While sharing more similarities than differences, the three models offered by the three different carriers do differ slightly. While T-Mobile is still playing the complete specs of its particular phone close to its chest, it is recognizable by its slightly rounded edges and brushed plastic rear casing. AT&T and Sprint, however, have been more forthcoming on the details of their offerings.

Sprint's Galaxy S II will be sold as the Samsung Galaxy S II Epic 4G Touch and boasts a 4.52-inch Super AMOLED Plus touchscreen - as will the T-Mobile model - compared to the 4.3-inch display found on AT&T's model. Both size screens offer 800 x 480 pixel resolution, so the AT&T unit does boast a higher pixel density. AT&T can claim the thinnest model at 8.89 mm (0.35 in), while the Sprint version measures 9.65 mm (0.38 in). The extra millimeters might be explained by the 1800 mAh lithium-ion battery found on Sprint's model, while AT&T's unit is packing a 1650 mAh battery.

Sprint will be first to offer the Samsung Galaxy S II (Epic 4G Touch) with a release set for September 16 and price of US$199.99 on a two-year contract. AT&T will follow with a September 18 launch date and pricing yet to be announced. T-Mobile is yet to announce pricing or release date details.

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