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Set up Google Voice Open the Google Voice app. Tap ☰. Tap Settings. Tap the toggle switch next to "Anonymous Caller ID".
.  Google Voice is a free app that allows you to place calls using a different number from your standard mobile number.  Before you use Google Voice, you need to download it from the App Store or Google Play Store.  When you place your first call using the Google Voice app, you will be asked to search for and select a number to use.  Follow the on-screen instructions to select a number to use with Google Voice. Google Voice numbers are not listed publically.  However, if you have posted your Google phone number online or give it out to other people, it may still be traceable back to you.  Use the following steps to make your hide your Google Voice number when making calls. The Google Voice app has a dark-green icon that resembles a phone.  Tap the icon on your home screen or apps menu to open Google Voice. It's the icon in the upper-left corner of Google Voice.  This displays the Settings menu. It's next to an icon that resembles a gear.  It's near the bottom of the Google Voice menu. It's below the "Calls" header in the Settings menu.  If the toggle switch is to the right, Anonymous Caller ID is turned on.  You can use Google Voice to call from a different number and keep it a secret.