What branch of engineering do you have? Someone posted here in reddit a while ago the idea of using a metronome watch to help speaking in a rythm, which is helpful. Is good for phone calls amd video calls. But in person, the vibration can easily be heard by others. Maybe in your future projects, develop a earphone that vibrates, or a watch with a silent vibration but that you can still feel? I know drummers have those, but they are huge.