Does imessage charge?

If the other party is also an iPhone user and uses mobile data or wireless network when sending text messages, then imessage is free.

IMessage can tell you whether the message has been delivered, and if the receiver has enabled the read receipt, you can also see the read receipt message of the message. When someone is replying, iMessage can also display status information so that you can continue the conversation naturally and smoothly. When the text bubble is blue instead of green, you will know that you are using iMessage instead of SMS, and you will receive a reply faster.