How does Apple's 5s mobile phone send messages in groups?

Apple mobile phone group messaging mode: iPhone mobile phone group messaging operation mode is divided into the following two types:

1. Add contacts in the address book: enter the information editing interface, click the+icon on the right of the recipient, and add contacts in the address book in turn. After adding, click the send button on the right side of the content dialog box to send it in groups.

2. Add contacts outside the address book: enter the information editing interface, manually enter the contact number, and then press line feed on the Chinese keyboard or press Enter on the English input method keyboard to continue adding the next number. After adding, click the send button on the right side of the content dialog box to send it in groups. Note: If there are both iMessage contacts and ordinary contacts in the group sending contact, it will be automatically converted into ordinary text to send.