AT&T had a big day on Sunday as it celebrated the launch of four new handsets for their robust smartphone portfolio. The carrier was most excited to unveil its first two LTE smartphones, the HTC Vivid and the Samsung Galaxy S II Skyrocket. Both devices run Android 2.3 on 4.5-inch screens and with eight-megapixel back cameras. However, the HTC Vivid has the slower 1.2GHz dual-core processor with a 540×960 screen. Meanwhile, the Samsung Skyrocket sports a dual-core 1.5GHz chip with a 480×800 screen. Oddly enough prices were left out for both devices, but AT&T has mentioned in the past that the Vivid would be priced at $200 on a contract and the Skyrocket at $250.

The party didn’t stop with the Skyrocket and the Vivid, as AT&T also unveiled Samsung’s two new Windows Phone 7.5 smartphones, the Focus Flash and the Focus S. The Focus Flash, being the more budget friendly model of the two, sports a 3.7-inch Super AMOLED screen, five-megapixel rear camera,front facing camera, and a 1.4GHz single-core Snapdragon processor. The higher-end handset of the pair, the Focus S, rocks the  same Snapdragon processor, a larger 4.3-inch Super AMOLED Plus screen as well as an eight-megapixel rear camera. Users will be pleased with both prices for these devices as the Focus Flash costs $50 on contract and $200 for the Focus S.

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