Nokia has sent out the invitation for the Microsoft Build Developer Conference scheduled on April 2, Wednesday, in San Francisco. The Finnish company is expected to focus again on the Windows Phone handsets at the upcoming event after officially unveiling their first Android phone, Nokia X, at the 2014 Mobile World Congress (MWC).

The invitation posted on Nokia's Conversations blog teased that there are "More Lumia" to arrive with the interactive graphic featuring different icons for the letter "O" in the word "more." Click HERE to see Nokia's invitation for the event.

The Windows Phone 8.1 is expected to be officially introduced at the Build event together with the Nokia Lumia smartphones running on the latest operating system like the Nokia Lumia 630, 635 and 930. "There are no details given about exactly what Lumia news will be given, but the 930 and 630 handsets look like a distinct possibility as well as the Lumia 635, thought to be a dual-SIM version of the 630," the Phones Review report noted.

According to the Recode report, Microsoft declared at the 2014 Mobile World Congress that the spring Windows Phone update will be adding support for the lower-end Qualcomm Snapdragon chips in order to prepare for the more low-cost models. The Nokia Lumia 630 is expected to be the affordable smartphone and one of the new ones packed with the Windows Phone 8.1 ready to replace its popular predecessor, the Nokia Lumia 620.

The leaked press image showed the Nokia Lumia 630 still sporting the Nokia trend on lively colour choices with the design bearing resemblance to the recently unveiled Nokia X Android smartphone. The Nokia Lumia 630 features and specs reported in 3g.co.uk include the 4.3-inch touch screen display with 854x480p resolution, the power of a 1.7GHz dual-core Qualcomm Snapdragon 400 processor, 1GB of RAM and a 5MP camera with the Nokia Lumia 635 version having LTE support.

The Nokia Lumia 635 will be the dual-SIM version of the Nokia Lumia 630 also pre-loaded with the Windows Phone 8.1 OS also expected to be officially unveiled with the other Windows Phone 8.1 devices such as the Nokia Lumia 930 and the rumoured new Nokia flagship, the Nokia Lumia 530.

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