You can also add a new contact from within the app itself. If a contact is already in your phone, it will show as a contact in your Messages app.

Start a conversation with one of your contacts If you no longer want Messages to be your default messaging app, you can uninstall the Messages app or change your default messaging app from your device's settings. In the list of apps, click Messages SMS Messages.When prompted to change your default messaging app, follow the onscreen instructions.To set Messages as your default messaging app, select an option: When you make Messages your default messaging app, you can review your text message history in the Messages app, and you'll only be able to send and receive new text messages in the Messages app. If your device has more than one messaging app, you can make Messages your default messaging app. For more information about how to manage your app permissions, contact your device manufacturer. Important: Your messages are stored in the SMS database on your device, and other apps may be able to access your messages. Important: Some of these steps only work on Android 6.0 and up.

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