What is the best use case for this smart watchstrap.

The smart watch strap we're developing lets you make calls with your fingertip. You can hear the voice simply by place your finger to your ear, while you speak through a mic embedded on the strap. Pair up with your Apple Watch, Pebble Watch or any sort of analog and smart watches, you can make a call and privately hear distinguished voice, without speakerphone or headset. How would you use it? Where do you think it is most needed?