[nradov]

The cell phone carrier market is the classic example of a "confusopoly" where the dominant market players make it as hard as possible for consumers to make fully informed decisions. None of the carriers actually has a monopoly outside of a few isolated areas.

https://en.wikipedia.org/wiki/Confusopoly

Acoustics make it impossible to do good noise cancellation using just an app. You really need a specialized microphone mounted directly on the headphones.

[petra]

Sure you need a high quality microphone on the earphone - but that's men's , could be very cheap in volume. And the rest is something interface chip on the phone, and than some digital logic which is cheap.