let sessionID = "12345" //you can set anything
let callView = UIView()// a UIView you want to show the calling view in
let callSettings = CallSettings.CallSettingsBuilder(callView: callView, sessionId:sessionID).setAudioOnlyCall(audioOnly: true).enableDefaultLayout(defaultLayout: true).build()
CometChat.startCall(callSettings: callSettings, userJoined: { (user) in
}, userLeft: { (user) in
}, userListUpdated: { (userList) in
}, audioModesUpdated: { (audioList) in
}, onUserMuted: {onUserMuted in
}, onCallSwitchedToVideo: {callSwitchVideo in
}, onRecordingStarted: {onRecordingStarted in
print("onRecordingStarted \(onRecordingStarted)")
}, onRecordingStopped: {onRecordingStopped in
print("onRecordingStopped \(onRecordingStopped)")
}, onError: { (error) in
print("OnError \(error!.errorDescription)")
}) { (call) in
print("onCallended \(call)")
}