How does Apple 7 judge that the other party has received the SMS?

All mobile phones can only know whether the sender sent it successfully or not.

When Apple's mobile phone sends, there will be a small green bar sliding from left to right. When swiping to the right, the phone will make a sound, indicating that the message has been sent successfully.

If the transmission is unsuccessful, there will be a hint of transmission failure, which just shows that your signal is not good.

If the other party shuts down, it is also prompted as above.

2. This problem can be found by trying two Apple phones.

Under normal circumstances, Apple has the function of receiving short messages.

This function requires the other party's Apple device, and the other party has opened the read receipt.

In Settings-Info-Open Read Receipt. As long as the other party opens it, you can see whether the other party has read it.

Similarly, if the other party does not turn on this function, there is no way to see it, only to see whether the information has been sent to the other party's mobile phone.

For example, for all mobile phones, open the "send status report" to know whether he has received it: when it was received, when the sender's mobile phone will prompt him to receive it; But for sending to Unicom or PHS, this will not work. If it is received or not, it will say yes.