WhatsApp will mark read messages with blue checks – update
WhatsApp will mark messages that recipients have read with two blue ticks. The company of the chat app confirms this on its own site. The new blue check marks therefore have a different meaning than the gray check marks that have existed for some time.
WhatsApp explains the meaning of the new check marks on its faq page, after a Softonic editor had the check marks spotted in the Android version of the app. The blue check marks mean that a recipient has actually read the message, but both phones must be running the version of the app that supports it.
The two gray checks only mean that the recipient’s phone has received the message, while a single check still indicates that the message has been sent. With the arrival of the blue check marks, WhatsApp users have certainty that a message has been read for the first time. The feature also works in group conversations, when all participants have read the message.
It is unknown how the function works, but it is believed WhatsApp will mark a message as read if the recipient has opened the app and viewed the conversation in which the message was sent. On iOS, Android and BlackBerry 10, among others, it is possible to read messages without opening the app.
Update 10:48: The blue check marks only appear when the user opens the chat message in the app; reading and then ignoring messages via the lock screen and the notification bar remain possible in iOS and Android.