This phone is designed to be as close to invisible as possible. Here's the details.
The microphone is a fake back tooth, and the headphones are (until i can come up with something more effectively hidden) small skin-coloured buds that slot into the ear. For neatness' sake, they may also act as anti-noise
devices. Many commands are issued to the phone by speaking, such as 'call Chris' - that is already baked.
The handset is actually more like a glove. It's utterly transparent, clings to the skin and has pores to allow sweat and air to pass through, so you almost can't tell you're wearing it. Rather than being pressure sensitive, it detects tension and compression. Ie, it detects the shape and movement of your hand.
You control the phone with gestures: to make a call, you might stick out your thumb and little finger in a 'phone' shape. To hang up, you move your hand in a horizontal slice movement, like a 'kill this' signal.
If you didn't want to dictate, then you would also use gestures to enter numbers and information, and to type text messages. The Skin Phone can be configured to recognise your favourite dialect of sign language, or it would come with a non-deaf-person's sign language for standard text entry (kind of like 'graffiti' input on PDAs).
Feedback on all of these would be spoken to you.