Charge the phone bill to the secondary phone card, will there be information on the main phone card?

The secondary card can charge the phone bill, and the phone bill charged to the secondary card of China Mobile can be shared with the main card.

1, SIM card?

GSM digital mobile phones are also called subscriber identification cards and smart cards, and they must be installed before they can be used. Digital mobile phone customer information, encryption key and user phone book are stored on the computer chip, which can be used to authenticate the identity of GSM network customers and encrypt the voice information when customers talk.

2.SIM card capacity

The capacities of SIM cards are 8K, 16K, 32K, 64K, 128K, among which large-capacity SIM cards above 5 12k are collectively called STK cards.