Make another call while already on a call
When you make another call while you're already on a call, your first call is automatically put on hold.
While on a call, tap
Do any of the following:
• Use the dial pad to enter a number.
• Tap above the dial pad to go to the Phone screen. Tap a contact.
To merge both calls and start a conference call, tap
To add more people to the conference call, repeat steps 1 to 3.