1. While on an active call, press the Volume keys to adjust call volume.
   
2. Tap Speaker to toggle speakerphone on / off.
   
3. Tap Mute to toggle mute on / off.
   
4. Tap Headset to toggle headset features on / off.
   
5. Tap Keypad to show the keypad.
   
6. Tap Hide to hide the keypad.
   
7. To add a call, tap Add call.
   
8. To place a call on hold, tap the Hold icon.
   
9. Tap the Noise reduction icon to toggle noise reduction on / off.
   
10. Press the Home key to return to the home screen.
    
11. To return to the call, touch and drag down the Notifications bar to reveal the menu.
    
12. Tap End call.