[Deep in the pad of Devero's finger, he'll be able to feel a very small, very hard node, like there's a tiny bead stuck in there.]

Think of it as a tiny radio. When it gets certain signals from my body, it sends an little electronic transmission to here. [With his other hand, he taps the Interface perched on his ear.] Depending on what app I've got activated at the time, that transmission tells my Interface to do something.