Walrus give you the possibility to do lazyload in a very simple way, and so optimise your SEO.
First you need to include Walrus.js to your project:

    <script src="www/assets/javascript/Walrus.js"></script>

And then set the lazyload to true with:

        lazyload: true

Now to lazyload a part of your website you just have to specify the data-lazyload attribute to an HTML tag.