Why/when do I have to tap twice to trigger click on iOS
I solved this issue by first detecting if it was an iphone, then binding the mouseup event to the function I was trying to call.
if ((navigator.userAgent.match(/iPhone/i)) || (navigator.userAgent.match(/iPod/i))){ $('foo').on('mouseup', function(){ ... }}
I tried other events but mouseup seemed to work best. Other events like touchend were firing even if the user was trying to scroll. Mouseup doesn't seem to get fired if you drag your finger after touching.
Credit David Walsh (and ESPN) for the iPhone detection. http://davidwalsh.name/detect-iphone