Events like touchstart or touchend do not work when attached to the window inside an IFrame on iOS devices.
Check out this straightforward example:
mainpage.html
<!DOCTYPE HTML>
<html style="height: 100%;">
<head>
<meta charset="UTF-8">
<title>Touch Test</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body style="height: 100%; margin: 0; overflow: hidden;">
<iframe style="width: 100%; height: 100%; border: none;" src="subpage.html"></iframe>
</body>
</html>
subpage.html
<!DOCTYPE HTML>
<html>
<head>
<meta charset="UTF-8">
<title>Touch Test</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
body {
margin: 0;
padding: 8px;
}
div.header {
margin-bottom: 8px;
}
div.text-entry {
font: 300 1rem/1.25 'Open Sans', 'Helvetica Neue', helvetica, arial, sans-serif;
color: rgb(64, 64, 64);
}
</style>
<script>
window.onload = function() {
function addEvent(event) {
var div = document.createElement('div');
div.className = 'text-entry';
div.textContent = new Date().toLocaleTimeString() + ' Event "' + event.type + '" detected';
document.body.appendChild(div);
}
window.addEventListener('touchstart', addEvent.bind(null), false);
window.addEventListener('touchend', addEvent.bind(null), false);
}
</script>
</head>
<body>
<div class="text-entry header">Try clicking/touching the viewport to see text entries added...</div>
</body>
</html>
Many have faced scroll and event issues on iOS in IFrames, but solutions seem elusive for the problem at hand.
I've set up a CodePen and a JSFiddle for experimentation, both demonstrating the same behavior within an IFrame.