AT&T today announced the LG Nitro HD, a new Android smartphone that supports AT&T’s Long Term Evolution 4G and HSPA+ networks, and includes a 4.5-inch AH-IPS (Advanced High-Performance In-Plane Switching) display with 1280 x 720 pixels for HD resolution. LG says the display offers 500 nit brightness, which lets it be used in direct sunlight, and RGB stripe pixels, which it says offer better color representation. Other features of the Nitro HD include a dual-core 1.5GHz processor, 8-megapixel camera, 4GB of built-in memory (plus microSD support), Wi-Fi Direct, and DLNA. It runs Android 2.3 Gingerbread. The LG Nitro HD goes on sale December 4 at company-owned stores and online for $249.99 with new agreement.