1. While on a call, tap the Mute icon to toggle mute on/off.
   
2. While muting is enabled, a Mute icon will be displayed in the notifications bar.
   
3. Tap the Speakerphone icon to toggle speakerphone on/off.
   
4. While speakerphone is active, a Speakerphone icon will be displayed in the notifications bar.
   
5. Press the Volume keys to adjust call volume.
   
6. Tap the Dialpad icon to bring up the Dialpad.
   
7. Tap the Menu icon to bring up more options.
   
8. Tap Hold to put the current call on hold.
   
9. Your current phone call is now on Hold. To Unhold the phone call, tap the Menu icon.
   
10. Then tap Unhold
    
11. To add a call, tap the Menu icon.
    
12. Tap Add call.
    
13. Tap the desired number to add to the call.
    
14. Tap CALL.
    
15. Tap Merge calls to enable 3 way calling.
    
16. The calls have been merged. To disconnect a call, tap the Menu icon next to the desired call.
    
17. Tap Finish this call in order to disconnect the desired phone call.
    
18. During a call, press the Home key to return to your home screen.
    
19. To return to your call, touch and drag down from the top of the screen to access the notifications tray.
    
20. Tap the notification to return to the call.
    
21. If desired, tap the End call icon to end the current call without returning to it.