How to send SMS from ipad to iphone?

1. It is recommended to check the settings-information-sending and receiving first, so as to ensure that the "How to contact you through iMessage" of all devices is the same.

2. Under normal circumstances, after new information comes in, as long as it is read on one device, there will be no reminder on the other device, but the content can be synchronized. (Only iMessage can be synchronized, not ordinary SMS).