Why did Apple's SMS become imessage?

Green is SMS, and imessage is blue.

Imessage is a major function of iphone, which is to send messages to each other for free when they meet on ios devices. Sending imessage is not a short message, but it needs a little traffic.

If you really want to turn off the imessage function, go to Settings-Messages, and then turn off a switch in imessage. All messages will be sent as regular messages.

There are many possibilities for iMessage to automatically transfer short messages:

1. The other party no longer uses iPhone or Apple products.

2. The other party manually closes the iMessage service.

3. Other iPhone or Apple products can't access the Internet.

Specific steps to change Apple's SMS to imessage format:

1. Find "Settings" on the mobile phone desktop and enter the "Settings" page of the mobile phone to proceed to the next step.

2. In the settings page, slide down the page to find "Information" and click.

3. Turn on the switch of iMessage to activate the sending and receiving function of iMessage.

4. After opening the iMessage function, click "Send and Receive" and log in to your apple ID account.