Work with multiple calls
During an established call, tap Add call to return to the main screen and dial another destination. The existing call is held while you start the new call. Available call capacity depends on your app and SIP service.

Select a call
When more than one call exists, the call screen shows a Select call control beside the red end-call button. Its badge shows the number of calls.

Tap Select call, then choose the call you want to use. The selector identifies the current call and the other calls. Use hold or resume as needed when switching.

Merge calls into a conference
With compatible calls established, tap Merge. If the app offers a choice, select the call to merge. The call screen displays Conference and the participants when the merge succeeds.

Split a conference
Tap Split calls. For a conference with several calls, select a participant from the list to remove that call from the conference. With two calls, splitting can happen directly. Use Select call to manage the resulting calls.

Return to a call or end it
If you are on the main app screen while calls remain active, tap the green Back To Call banner. Use the red phone control to end the selected call; when the selected item is a conference, that action applies to the conference.