If you accept a new call when you’re already on a call, you can switch between the two callers or merge the two calls into a single conference call. You can also set up a conference call with multiple callers.
Contact your wireless service provider to learn whether they support conference calls and how many participants you can include.
When you’re connected, touch Add call.
When you’re connected, touch Merge calls.
During a conference call, touch Manage to drop a conference call participant or to talk privately with one of the participants.