How to use the speakerphone
Short answer
Use your speaker as a speakerphone while connected. Push the control knob once to accept or end a call, or twice to reject.
Willen II comes with a built-in microphone that let you use it as a speakerphone:
While connected, any incoming call will sound to the speaker.
To accept or end a call, push the control knob once.
To reject a call, push the control knob twice.
Push the Bluetooth button to toggle the call between the speaker and your phone.