Google Now allows users to send messages via Hangouts using voice commands. When the users say the message, the Android device recognizes it and converts speech to text and then sends it for them.
If you want to send a Hangouts message using Google Now, all you need to say is “OK Google, send a Hangouts message” and the it asks you whom to send your message to and later it asks what your message would be. After converting it to text, Google Now also asks your confirmation to send the message.
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