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It's the green and white chat bubble icon with a phone receiver inside. You'll find it on the home screen or in the app drawer. This method will help you disable the feature that allows your contacts to see when you've viewed their messages. It's at the top-right corner of the screen. " It's in the "Messaging" section. Once the box is blank, your contacts will stop seeing blue check marks when you've read their messages. You also won't see blue check marks when they've read yours.
Open WhatsApp. Tap . Tap Settings. Tap Account. Tap Privacy. Remove the check mark from "Read receipts.