Computer Science Mojo

If your JavaScript touch code works perfectly on ios but does nothing on Android, "e.pageX" might be the problem. "e.pageX" simple does not work on Android and returns "not a number", though it works fine both on desktop browsers and ios Safari. Use "e.targetTouches[0].pageX" for Android to fix this problem.

Encountered this problem when making Learn Huge :
"e.targetTouches[0].pageX" is Android specific, so to ensure cross platform compatibility:

1. Check if it's Android or not:

var isAndroid = false;

if( (navigator.userAgent || navigator.vendor || window.opera).match( /Android/i ) ){
    isAndroid = true;
}

2. Use the correct one depending on platform:

if(isAndroid){
    nowX = e.targetTouches[0].pageX - this.offsetLeft;
    nowY = e.targetTouches[0].pageY - this.offsetTop;
}
else{
    nowX = e.pageX - this.offsetLeft;
    nowY = e.pageY - this.offsetTop;
} 

After changing to "e.targetTouches[0].pageX", Android Chrome takes the code happily.