Follow the steps below depending on your device.

• For iPhone: Go to Settings > Mobile Service > Wi-Fi Calling > On
  If you use more than one SIM on your iPhone then select SIM > Wi-Fi Calling > On
• For Android: Go to Settings > Connections > Wi-Fi Calling > On (may vary slightly by phone)

Device compatibility can vary by manufacturer. Right now, Apple and TCL phones with the latest software updates are ready to use Wi-Fi Calling on the GO network. More brands, including Samsung and Google, will be joining soon through upcoming updates.