In a recent announcement, AT&T has surprised windows phone fans and confirmed the official availability of two most-awaited Windows smartphones, the Nokia Lumia 900 and the HTC Titan II. According to Bloomberg, the leading telecommunication services provider in wireless technology would be launching HTC Titan II 4G LTE windows phone along with the Nokia Lumia 900 on April 8 this year.

Powered by Windows Mango, Lumia 900 is the second Lumia phone to release in the US after Lumia 710. AT&T has confirmed that the phone will be available at a retail price of $99.99. AT&T will charge a full price of $449.99 for the 4G LTE capable Nokia Lumia 900. In contrast, HTC Titan II, equipped with a larger screen, would be costlier by $100 and will be offered by AT&T at a full retail price of $549.99.

Further, AT&T has also confirmed that the new high-gloss white-colored version of the Nokia Lumia 900 handset will start hitting  shelves on April 22.

So what will it be? Nokia Lumia 900 or HTC Titan II? Which Windows Phone 7.5 Mango is it going to be for you? Here is a spec comparison between the two smartphones and how they will stack up against each other in the Windows war.

Display and Dimensions

The Lumia 900 sports rounded edges and flat top and bottom look, has a vivid display of 4.3-inches Clear Black AMOLED with 480 x 800 pixels of resolution and is backed by strong, scratch-resistant Corning Gorilla Glass. Further, Nokia's latest handset will have dimensions of around 127.8 x 68.5 x 11.5mm with a weight of 160 grams. On the other end, HTC Titan II boasts a wickedly larger 4.7-inches Super LCD display with 480 x 800 pixels of resolution and it would come in the dimesions of 132 x 69 x 13mm and would weigh around 147grams.

Camera

The Lumia 900 packs the same 8-megapixel primary camera as the Lumia 800, complete with a Carl Zeiss lens at 3264 x 2448 pixels of resolution including features like autofocus, geo-tagging, dual LED flash and 720p video capture. Lumia 900 features the addition of a 1-megapixel rear facing camera, from its predeccesor.

On the other hand, HTC Titan II has to offer what appears to be a much more satisfying Windows Phone camera experience, thanks to an impressively 16-megapixel primary camera with a wide-angle lens, backside-illuminated sensor and a 4640 x 3480 pixels of resolution. Further the Titan II also boasts fast wide-angle lens (f2.6, 28mm), an additional front-facing 1.3 megapixels camera to make video calls and It can also capture video in 720p HD and features autofocus, dual LED flash, red eye reduction, image stabilization, panoramic shot mode and burst shot mode.

Processor and RAM

Both phones are clocked with Qualcomm Scorpion processor; however, there is a difference. Nokia Lumia 900 runs a 1.4GHz clock-speed just like its smaller kin, this time, however, it uses the MSM8255T Snapdragon chipset, along with the same Adreno 205 graphics processing unit (GPU). While HTC Titan II has a slightly higher clock-speed at 1.5GHz, it also uses the same MSM8255T Snapdragon chipset and GPU combination. Both the devices run at 512MB RAM.

Operating System

Both the smartphones, the Nokia Lumia 900 and the HTC Titan II have a common operating system. They both run on Windows Phone 7.5 Mango, which boasts features like dynamic Live Tile Information, Twitter and LinkedIn integration in the People hub, Facebook-events integrated calendar, threaded e-mail conversations support, visual voicemail, Outlook tasks support and much more. Other features of the OS include Shazam-like audio recognition, turn-by-turn Bing Maps navigation with voice guidance, Skydrive and Office 365 documents synchronization with PDF support, Microsoft Lync support, animated picture tiles, People/Groups gallery with Skydrive and Facebook sync, People Hub-integrated photo management, Zune SmartDJ multimedia mix support, video aspect ratio control capability while playback and more.

Storage

Nokia's Lumia 900 has the same memory setup as its predecessor, which means 16GB of internal storage and no card slot. Likewise the Titan II has the same setup as the original Titan, which incidentally is also the same as 16GB of internal storage without any microSD storage slot.

Wi-Fi, Bluetooth, WLan

Both the smartphones sport an 802.11 a/b/g/n Wi-Fi connection and have 2.1+A2DP Bluetooth, the Focus S has 3.0+A2DP, EDR Bluetooth.

Battery

The HTC Titan II has a standard Li-lon 1730 mAh battery. Compared to this, the Nokia Lumia N900 has a standard Li-lon 1800 mAh battery with up to 300 hours of stand-by, 7 hours of talk time and 60 hours of music play.