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Open Viber on your Android. Tap the person you want to message. Type a message and send it. Look at the gray text below your message.
It’s the purple icon with a white chat bubble and phone receiver inside. You’ll usually find it on the home screen or in the app drawer. This opens a conversation. Your message now appears at the bottom of the conversation. This is how you’ll find out if the person has seen your message.  If there is no gray text below your message, this means the message has been sent but hasn’t yet made it to the person’s Viber app. They may not have Viber running, or their phone may be off. If you see “Delivered,” this means the message was delivered to Viber but the recipient hasn’t opened it yet. If you see “Seen,” this means the person has seen your message.