After using android phone for 2-3 years, I wanted a change and opted for Nokia Lumia 520 being entry level windows phone. The phone is with windows 8 OS, 512 MB RAM, 1GHZ dual core processor and 4 GB phone memory. Performance of phone is excellent. We can have multitasking very easily. I found it better compare to android phone as in WIndows 8 phone applications are closed once task is completed unlike android phones where all applications remain on consuming battery unnecessarily.
No. of applications available are not as much as in android phone. However, my requirement is almost fulfilled. Collection of songs on Nokia Music is awesome. Camera quality is also quite good.Cons for this phone is lack of equalizer in music player, could not find any application for data counter for internet usage and we can not open office files from SD card in windows phone. only way to open office file is to change the file extension to .sd and can open with the paid application File Explorer.
Overall, this is a value for money smart phone.