Did Apple get the imessage message?

Imessage is used to send messages directly to Apple users for free. You can think of it as something like WeChat. Imessage needs to be connected to the Internet to send information. If the other person's mobile phone is also Apple, then the information you send him, if you both have the imessage function enabled and have the Internet, is free. The imessage message seen in the information record is blue, and the ordinary charging SMS is green.