Speaker Button
Tap here to turn the speakerphone on or off. The button is blue when it's on.
Mute Button
Tap here to mute the microphone during a call. The button is blue when the microphone is muted.
Bluetooth Button
Tap here to switch between a Bluetooth device and the phone. The button is blue to indicate that the call is using a Bluetooth device. The button is gray when no Bluetooth device is available