It seems that androids WebView doesn't like video tag.

Here is Android code which worked for me:

        mWebView.setWebViewClient(new WebViewClient() {
            // autoplay when finished loading via javascript injection
            public void onPageFinished(WebView view, String url) {
                mWebView.loadUrl("javascript:(function() { document.getElementsByTagName('video')[0].play(); })()");

        mWebView.setWebChromeClient(new WebChromeClient());

Where WebChromeClient we need to handle javascript methods, and it seems that autoplay in WebView doesn't work.

Also, mWebView is: private WebView mWebView; (I took example of WebView based application)

HTML code looks like:

<video autoplay loop>
	<source src="" type="video/mp4">