SAMSUNG has been wasting his money in manufacturing j series phones simply a waste of money for the consumers also.
Since they have launched the first j series phone and till now J7, they are giving the same camera features front 5 mp and back 13mp with no improvement in camera, same display, a lil bit change in processor but it doesn"t matter, hangs a lot, heats a lot actually all samung phones hangs.
Even after updating it the problem will not sort out.So I would recommend don"t by samung phones but s6 and s7 are exceptional cases they are best.