Lenovo k4 note very useful mobile, sound very good and display full hd, bt battery not good, back camera good, front camera not good, weight 159gm, good weight, dual sim and memory card, this mobile is 4G, 3GB Ram and 16GB internal memoryexpandable up to 128GB, 3300mah lithium-ion battery providing talk-time of 26hours.i am use this mobile, good mobile?