Test page to see how far away from a link you can touch while still tapping it.

page.html

<meta name="viewport" content="initial-scale=1, maximum-scale=1">
<script src="http://code.jquery.com/jquery-2.1.3.min.js"></script>
<style>
div {
    position: absolute;
    background-color:green;
    left: 100px;
}

#a {
	top:100px;
    width: 10px;
    height: 10px;
}

#b {
	top:200px;
    width: 30px;
    height: 30px;
}

#c {
	top:300px;
    width: 50px;
    height: 50px;
}

#d {
	top:400px;
    width: 100px;
    height: 100px;
}

</style>
<h1>Test</h1>

<span>hi</span>
<div id="a"></div>
<div id="b"></div>
<div id="c"></div>
<div id="d"><a href="javascript:">Link</a></div>

<script>

$('body').on('touchstart', function (event) {
	$('span').text(event.originalEvent.touches[0].clientX + ', ' + event.originalEvent.touches[0].clientY)
})

$('#a, #b, #c').click(function(event) {})

</script>