How can I autoplay media in iOS >= 4.2.1 Mobile Safari?

1.js

There is one way to play the video/audio file automatically on 4.2.1. Create an iframe and set its source to the media file's URL and append the iframe to the body. It'll be autoplay.

var ifr=document.createElement("iframe");
ifr.setAttribute('src', "http://mysite.com/myvideo.mp4");
ifr.setAttribute('width', '1px');
ifr.setAttribute('height', '1px');
ifr.setAttribute('scrolling', 'no');
ifr.style.border="0px";
document.body.appendChild(ifr);

source: http://stackoverflow.com/questions/4259928/how-can-i-autoplay-media-in-ios-4-2-1-mobile-safari