Phone icon will display in the Notification bar.In this tutorial, you will learn how to:
• Access in-call options
• Add favorite contacts
• Use your phone while on an active call
• Create a conference call
• Decline a call with a text message
• Enable/disable call waiting
• Swap between active calls
Access in-call options
While on an active call, the following options will be available:
• MUTE/UNMUTE: Select the Mute icon.
• SHOW/HIDE KEYPAD: Select the Keypad icon.
• ENABLE/DISABLE SPEAKERPHONE: Select the Speaker icon.
• ADD CALL: Select the More icon then select the Add call icon and follow the prompts.
• HOLD/RESUME CALL: Select the More icon then select the Hold icon.
• END CALL: Select the End call icon.
Add favorite contacts
From the 
Phone app, select the Contacts tab, then select the desired contact. Select the Favorite icon to add the contact to your favorites list.
Phone app, select the Contacts tab, then select the desired contact. Select the Favorite icon to add the contact to your favorites list. 
From the Phone app, select the Favorites tab to view your favorite contacts. Select the desired contact, then select the desired call method.
Use your phone while on an active call
While on an active call, swipe up from the bottom of the screen to access the home screen. To return to an active call, swipe down from the Notification bar, then select the active call notification.
Note: Alternately, to return to an active call, select the contact icon then select Back to call. When put on hold by a business, Google Assistant monitors the call and lets you know when they’re back and ready to help. US only. English only. Toll-free numbers only. May not detect every on-hold scenario.
Note: Alternately, to return to an active call, select the contact icon then select Back to call. When put on hold by a business, Google Assistant monitors the call and lets you know when they’re back and ready to help. US only. English only. Toll-free numbers only. May not detect every on-hold scenario.
Create a conference call
From an active call, select the 
More icon then select the Add call icon and follow the prompts. To end a call, select the End call icon.
More icon then select the Add call icon and follow the prompts. To end a call, select the End call icon.Note: When creating a Conference call, after connecting with a second caller, you will need to select Merge calls to combine the separate phone calls. The End call icon is the same icon in a single call or conference call.
Decline a call with a text message
When receiving a call, select Message to decline the call and send a text message. Select the desired text message to send, or select Write your own... to write your own.
Note: To create or edit text message replies, from the home screen, select the Phone app > Menu icon > Settings > Quick responses > desired message to edit.
Phone app > Menu icon > Settings > Quick responses > desired message to edit.
Enable/disable call waiting
Call waiting allows you to accept additional incoming phone calls and put a currently active call on hold. To enable this feature, from the Phone app, select the Menu icon > Settings > Calling accounts > desired SIM > Additional settings > Call waiting switch.
Menu icon > Settings > Calling accounts > desired SIM > Additional settings > Call waiting switch.
Swap between active calls
While call waiting is enabled and a call is put on hold, select the More icon then select Swap from the in-call options to return to the held call.
More icon then select Swap from the in-call options to return to the held call.
Tips
To learn about calling or using your device in other countries, visit the AT&T International website.