The Nokia Lumia 710 (T-Mobile) costs just $50 which is a good deal for a well rounded smartphone. However Walmart is taking it to the next level by offering the device for free.You can choose between the black and the white and you will have to sign a new 2-year contract with T-Mobile to get the subsidised price. If you are looking to extend an existing contract you can also do so by paying $50. You can also avoid the commitment and get the device for $380 at the contract free price.
The Nokia Lumia 710 for T-Mobile which is a variant of the original Nokia Lumia 710 features the same 3.7-inch ClearBlack WVGA touch display, 5MP camera capable of 720p HD video and is powered by a 1.4 GHz processor.
If you are thinking of a higher end device you can also consider the Nokia Lumia 900 which will soon be available on AT&T.