More specifically, it is a rocker switch. One side is for dit, the other for dah. It makes the dits and dahs unambiguous, and easy for someone to quickly learn to use. I don't know of any phones with a rocker switch on them.

I thought it would be a fun thing to have on a phone.

My phone has a physical Ring/Vibrate/Silent slider. Fairly big deal for a modern smartphone (sadly)

Really nice to be able to shut it up with wet hands.

That is kind of interesting actually. Thanks for sharing.