Nokia is not a famous company for manufacturing Windows mobile phones. however they have started it and in the industry, it's a quite popular topic. even now, Nokia is the largest mobile phone manufacturer in the world. so this would be a big potential for the Windows Phone 7 OS. actually Nokia Lumia is a mobile phone series and Lumia 900 is a one of the very first device in this series.
Nokia Lumia 900 has a classic Nokia mobile look and it has a 4.3 inch AMOLED capacitive touchscreen. the screen resolution is 480 x 800 pixels which is common in most of the phones. it has 16GB internal memory and doesn't support memory cards. Lumia 900 has a 8MP camera and it supports 720p video recording at 30fps rate. like in any other Nokia phones. the camera lens made by Carl Zeiss optics. also this camera has dual LED flash. Lumia 900 has a 1.3MP front camera for video calling and you can also take pictures with it.
Nokia Lumia 900 runs with Microsoft Windows Phone 7.5 Mango OS. it powered by a 1.4 GHz Scorpion processor and has a 512MB RAM. this phone has a browser which supports HTML5 so you can visit any new mobile website. due to some reason, this phone only supports micro SIM cards. it has a 1830mAh battery, which will be sufficient for a this kind of phone.