I used Nokia Lumia 520 with red back cover having very great interface, animation, best screen touch quality, sound system, and specially the camera of 5mp. I used it for over 2 year with best experience. It full fill my need. It has great battery back. Low cost with great quality phone. If you want to purchase a new smart phone I will greatly suggest you about Nokia Lumia 520.Lumia phones with operating system of windows is having great experience than android smart phones. Store of windows having great application and games which are greatly satisfactory.