I can never remember. The good ones also switch between greyish being off and some color (e.g. green or blue) when on. But not all of them change color, so I

I can never remember. The good ones also switch between greyish being off and some color (e.g. green or blue) when on. But not all of them change color, so I tend to toggle them to see if this one of the colored ones -- and thereby confirm what setting it was on. (ps. In general I do like material and flat designs, it's just these checkboxes I find hard to read)