Touch events and mouse clicks are handled very differently between browsers and devices. I discovered this on a PhoneGap app when I wanted the user to be able to drag their finger and draw on the screen. X,Y coordinate seeking code I finally landed on below. Note that some devices, including my Nexus 10 with Paranoid return a touches collection off of the touchdown and touchmove events. This is not present on any of the other browsers or devices I tested.
function getCoordinateFromEventCrossBrowser(e, which) { var retval = 0; if (!e) var e = window.event; if (e.touches) { e = e.touches[0]; } if (which.toUpperCase()=="X") { if (e.pageX) { retval = e.pageX; } else if (e.clientX) { retval = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft; } } else if (which.toUpperCase()=="Y") { if (e.pageY) { retval = e.pageY; } else if (e.clientY) { retval = e.clientY + document.body.scrollLeft + document.documentElement.scrollLeft; } } return retval; }