auto: Automatically select the network to call sim. To activate this function you must enter a phone number of phone sim 1 and
sim 2 . The program will automatically detect the network of 2 sim (only in VietNam) .
SIM1: Using sim 1 for all calls.
SIM2: Using sim 2 for all calls.
Mode SIM1, SIM2, used when you want to use one sim 3G to access the internet and another sim to call.
off: Temporarily disable programs