HTML5 Canvas Animated Images Don't Load in Mobile Device Browsers

var c = document.getElementById("c");
var ctx = c.getContext("2d");

/*$("canvas").mousemove(function (event) {
    imj.x = event.pageX - 80;
    imj.y = event.pageY - 80;
});*/

function img(image, x, y, sorc) {
    image.onload = function () {
        ctx.drawImage(image, x, y);
    }
    image.src = sorc;
}

var imj = {
    img: new Image(),
    x: 0,
    y: 0
};
function render() {
    ctx.clearRect(0, 0, c.width, c.height);
    img(imj.img, imj.x, imj.y, "http://ift.tt/1A60oA1");
    imj.x += 1;
    imj.y += 1;
}

setInterval(function () { render(); }, 40);

When I load this code (along with the HTML), it works fine on my laptop, but on my Nexus 7, the image shows up once and then disappears. And if I make the image stay in place, it does show up on my tablet. Why? (you can try it yourself or see all the code here http://ift.tt/1A60mrH)