How to properly indicate that a chat message is sent-received-seen? The WhatsApp way?

Steps

1. One grey checkmark - Your message was successfully sent.
2. Two grey checkmarks - Your message was received by your recipient's phone.
3. Two blue checkmarks - Your recipient read your message on WhatsApp.

1. How do you know if a WhatsApp message has been received and read?

How do you know if a WhatsApp message has been received and read?

Two blue check marks appear when all participants in the group have read your message. For any message that you send, you'll be able to see a message info screen, displaying the details of when your message was delivered, read, or played by the recipient.