This read-only property indicates the number of items (touch points) in a TouchList.
Syntax
var numTouches = touchList.length;
Return value
numTouches
The number of touch points in touchList.
Example
This code example illustrates the use of the TouchList interface's item method and the length property.
target = document.getElementById("target");
target.addEventListener('touchstart', function(ev) {
// If this touchstart event started on element target,
// set touch to the first item in the targetTouches list;
// otherwise set touch to the first item in the touches list
var touch;
if (ev.targetTouches.length >= 1)
touch = ev.targetTouches.item(0);
else
touch = ev.touches.item(0);
}, false);