If you want to buy mobile first of all think about your need and your budget. When buying mobile always compare your product with available options. And think about RAM, ROM, Battery back up. Battery backup should be atleast more than 3000 mah because it is very important part of your mobile. Battery can keep you online every time. Second aspect internal storage and processer also worth noting. If you are interested in watching movies than screen size will also be important aspect. Collectively you should consider all features.