How to Send Read Receipts in iMessage?
When you send message to your friend, you may want to know if he/she had read the message. Now Apple enables you to know the message status. You can open the conversation window, tap the circle with “i” on top right corner, you can see “Send Read Receipts”, just turn on the switch. This setting will be synchronized in the iMessage on Mac, iPad and iPhone, but won’t change the settings on other devices.