
Many people appreciate this read receipt through blue tick marks. When your WhatsApp message will be read by your friend, the double gray ticks will turn into double blue ticks. This feature was implemented by the way of showing double light blue tick icon in the bottom-right corner of the WhatsApp message bubble. In group chats, these blue symbols only show when everyone in the conversation has read the message.WhatsApp recently launched a new feature that allows the sender of message to know when his message is read by the receiver.

When you send a message, the recipient will see those blue check marks if you read it and don't have read receipts disabled. The recipient may be able to view your message in a notification which would not show up as read. Two blue check marks mean the recipient has read your message, so the conversation had been opened and looked at. In group chats, the double gray check marks show when everyone in the conversation has received the message. Those won't appear next to any received messages. A single gray check mark means your message was sent, and a set of gray check marks means it was delivered. WhatsApp has a system of check marks that appear by every single message you send and receive, including text, photos, videos, and audio files.

WhatsApp, like other popular messengers on iOS and Android, shows when recipients have read your sent messages with a blue double check mark indicator.
