The LG Nitro HD, which was made available on AT&T's network from Dec. 4, is expected to face heavy competition from the HTC Rezound, which was made available on Verizon's network from Nov. 14.

The Nitro HD, which takes advantage of LG's new proprietary True HD technology, comes with a 4.5-inch AH-IPS (Advanced High-Performance In-Plane Switching) display that supports resolutions up to 1280 x 720 pixels and offers unrivaled color accuracy, brightness, battery efficiency and performance.

LG said Nitro HD's 500 nit display luminance allows for clear viewing in direct sunlight and the RGB stripe pixels deliver incredibly accurate true-to-life color rendering. It is the first smartphone in AT&T's portfolio with a true high definition screen and is the third 4G LTE smartphone for AT&T customers.

The Nitro, which runs on Google Inc.'s Android 2.3 Gingerbread OS, has a dual-core 1.5 GHz Scorpion processor, 4.5-inch True HD AH-IPS display, has 1GB of RAM, 4GB of internal memory plus an included 16GB microSD card, an 8 megapixel rear-facing LED flash camera with 1080p video capture and a secondary front-facing camera for video calls.

On the other hand, the HTC Rezound, which runs on Android 2.3 Gingerbread OS, is said to be the only phone in the United States with Beats Audio integration. The HTC phone is also known as HTC Vigor, HTC ThunderBolt 2, HTC Droid Incredible HD and HTC ADR6425.

Apart from this, the Rezound sports a 4.3-inch super LCD screen, 1.5GHz dual-core Qualcomm Snapdragon MSM8660 processor and Adreno 220 GPU, features an 8 megapixel camera in the rear and a 2 megapixel camera in the front.

Will the Nitro HD feel the pressure of the Rezound or will the LG smartphone outrun its competitor?

Let's take a look at the specifications of both the phones:

Display: The Nitro HD touts a 4.5-inch True HD AH-IPS (Advanced High-Performance In-Plane Switching) capacitive touch-screen with 1280 x 720 pixels resolution at about 326 ppi pixel density. On the other hand, the Rezound has a 4.3-inch screen with super LCD display which provides 1280 x 720 pixel resolution at about 342 ppi pixel density.

Size: The Nitro HD comes with 5.27 x 2.67 x 0.41 inches dimension and weighs 4.5 ounces. On the other hand, the Rezound comes in 5.08 x 2.58 x 0.54 inches dimension and weighs 6 ounces.

Processor: The Nitro HD features 1.5GHz Scorpion dual-core processor, Adreno 220 GPU, Qualcomm APQ8060 processor with 1GB RAM. On the other hand, the Rezound features 1.5GHz Scorpion dual-core processor Adreno 220 GPU, Qualcomm MSM8660 Snapdragon processor with 1GB RAM.

Camera: Both smartphones sport rear-facing 8-megapixel cameras with 1080p video capture capability. The Rezound has a dual-LED flash camera, while Nitro HD has a single LED flash. The Rezound has a 2 megapixel front-facing camera for video calling while the Nitro HD has only a 1 megapixel camera .

3G/4G: The Nitro HD has HSDPA 21 Mbps, HSUPA 5.76 Mbps and supports 4G LTE. On the other hand, the Rezound has Rev. A, up to 3.1 Mbps and LTE Class 13.

Operating System: Both smartphones have the Android 2.3 Gingerbread operating system with the promise of an upgrade to Google Inc.'s latest smartphone OS, Android 4.0 Ice Cream Sandwich. The Android Head of Engineering, Mike Claren, announced the new OS - Ice Cream Sandwich - as Google's most ambitious release to date.

User Interface: The Nitro HD comes with LG's custom user interface, while the Rezound uses HTC Sense 3.5 version user interface.

WLAN/Bluetooth/USB: The Rezound supports Wi-Fi 802.11 a/b/g/n, DLNA, Wi-Fi hotspot along with Bluetooth 3.0 version with A2DP and microUSB (MHL) 2.0 version. On the other hand, the Nitro HD has Wi-Fi 802.11 b/g/n, Wi-Fi Direct, DLNA, Wi-Fi hotspot, Bluetooth 3.0 version with A2DP, HS and microUSB 2.0 version.

Storage: The Nitro HD has fixed 4GB of internal storage with a 16GB microSD card included in the package that can be expanded up to 32GB. However, the Rezound has an internal 16GB storage with a 16GB microSD card included in the package that can be expanded up to 32GB.

Battery: The Nitro HD comes with a standard Li-ion 1830 mAh battery. On the other hand, the Rezound comes with a standard Li-ion 1620 mAh battery that gives more than 6 hours 24 minutes of talk time and 261 hours of standby.

Pricing: The LG Nitro HD is priced at $149.99 with a two-year AT&T contract in selected areas, while the Rezound is priced at $299.99 with a two-year Verizon Wireless contract.

Editors' Rating: The Nitro HD scores over the Rezound in technology editors' ratings. PCMag has a score of 4.5 out of 5 stars for the Nitro HD, while the Rezound scored 4. CNET rates both smartphones with 4 stars.