Some people are mentioning that this doesn't work on iOS, and that's because Apple doesn't have WebGL available in mobile versions of Safari.

But it is. This post by Nathan de Vries [0] shows how you can hack the UIWebView to enable WebGL contexts in your iOS apps. You have to get a little more creative these days (the compiler has gotten stricter about private types and functions), but all it takes is something like this:

    -(void)setWebGLEnabled:(BOOL)enableWebGL forWebView:(UIWebView *)uiWebView
    {
        id webDocumentView = [uiWebView performSelector:@selector(_browserView)];
        id backingWebView = [webDocumentView performSelector:@selector(webView)];
        [backingWebView performSelector:@selector(_setWebGLEnabled:)
                             withObject:[NSNumber numberWithBool:enableWebGL]];
    }

It should go without saying that code like this will not make it into the app store.

[0] http://atnan.com/blog/2011/11/03/enabling-and-using-webgl-on...