Perhaps it exists already, in which case please let me know why everyone doesn’t have one. But as I was listening to a guy answering his cellphone earlier today in a Beijing coffee shop and then, as everyone seems to do, automatically raising his voice to a shout, I thought: Why don’t I shoot him now? It’s what everyone around him wants. No that’s not what I thought. I thought: Why do we do this? Why is it so hard for us to be aware that when we speak on cellphones we tend to speak louder than we would when we’re not on the phone? And why don’t we realise this, and tone down our voice accordingly? (And, come to think of it, why don’t the people around us make us painfully aware of how loud we’re being?)
There must be an answer to this. I would have thought this would be quite simple: a sensor built into our cellphones that tells us when our voice is too loud, and informs us accordingly. So when we start yelling, a voice says into the earpiece “Your voice is louder than those around you. Your voice is louder than those around you” in an endless loop until our voice has returned to socially acceptable levels. Ignoring it would result in the person on the other end being informed politely that their interlocutor has failed to lower his voice and the call is being terminated. Efforts to disable this function would be met by a polite voice saying “deactivating this feature is not possible” along with a mild but noticeable electric shock administered to the user.
That should do it.