Can the primary card receive information from the secondary card?

Unable to receive secondary card information.

If it is a dual-card dual-standby mobile phone, what is the difference between the primary card and the secondary card?

The function of the main card is more and more perfect than that of the auxiliary card, and different versions are different.

If it is a mobile phone card, the difference between the main card and the auxiliary card: there is not much difference in the use of functions, and the expenses are paid by the main card, so the main and auxiliary card package is more suitable for family members.

The difference between the main card and the auxiliary card of dual-card dual-standby mobile phone, and the difference between the main card and the auxiliary card in the operator package;

If it is the first generation, it is necessary to distinguish between the main card and the auxiliary card of the dual-card dual-standby mobile phone. Older dual-card dual-standby mobile phones strictly distinguish between the main card and the auxiliary card. Generally speaking, the main card can make phone calls, send and receive short messages and surf the Internet, while the auxiliary card can only be used to make phone calls and send and receive short messages.

Because of the early dual-card dual-standby mobile phones, the main card slot only supports 4G and 3G networks, and the auxiliary card slot only supports 2G networks. If you want to switch between the main card and the auxiliary card, you need to turn off the phone, take out the SIM card slot, and then change the positions of the two cards.

The second generation dual-card dual-standby mobile phone no longer distinguishes between card slots. Two mobile phone cards can have a primary card and a secondary card in the system at will, but only the primary card can access the traffic network, and the secondary card can only use the 2G network. And in the process of switching between the primary and secondary cards, the mobile phone may need to re-register the network or even restart.