Previously, users had to click into a message and look at it to tell what its status was.
WhatsApp communicates whether a message has been read through a series of ticks: one means that the message has sent, two grey ones mean that it’s arrived on the recipient’s phone, and two blue ticks means that the recipient has read it.
The update is found in the new released version of WhatsApp, which should be available for update now.
More about: