Ask HN: why Apple uses a hardware switch for iPhone's silent mode?

My theory: its state can be detected by touch alone and toggled without having to look at the device. This is very convenient when it's in one's pocket or bag, especially when it's already making noise.

There additional benefits: you get one additional hardware button (or in this case, switch) that can be remapped to other functions. iOS does this for the screen rotation lock, where it again pays off immensely: when the screen is already in an awkward rotation, not many people will want to poke around an on-screen menu to get the screen to re-orient.

I think there is also a sense of trust, in terms of users worrying that they have clicked the right buttons in the UI to enable silent mode, if they get it wrong, a phone goes off at a very problematic time. With the hardware switch it is a very definite on/off silent mode.