Hi, I wanna upgrade my samsung J5, but don't know how. I need more space, so what sd card I should buy? Expensive better than cheap? And how much size of GB I need, or what size of card is recommended? One dumb question, but I wanna know, can I upgrade phone ram, or other components, make it run faster, and etc...? Also I wanna know should I need make factory reset, and upgrade phone freshly?