3d case for iphone with case,charger,speaker function external stereo speaker,enjoy music when charging Intelligent switch 1,product series: ... 4/4S: with protecter case,emergency charger and speaker function. (2)External stereo speaker,enjoy music during charging (3)intelligent switch between ... sign can switch for sound between iphone 4/4S and speaker. lightning sign : still press the key 3 seconds,the ...