On mobile devices, using on-click isn't good enough. Tapping the touchscreen will fire a simulated click event, but only after a 300 millisecond delay, which makes your app feel sluggish. It also causes the tapped area to highlight, which in most cases looks a bit messy.
Instead, use on-tap. When you tap an area, the simulated click event will be prevented, and the user's action is responded to instantly. The on-tap event also differs from on-click in that the click event will (frankly rather bizarrely) fire even if you hold the mouse down over a single element for several seconds and waggle it about.
Pointer events are also supported, as is pressing the spacebar when the relevant element is focused (which triggers a click event, and is good for accessibility).