add lazy loading to WP, more info at http://plugins.jquery.com/project/lazyload

jQuery Image Lazy Load WP

Frank Goossens

Optimizing Matters

EricJohnsonGuru

Eliminate Render-blocking Javascript in above-the-fold content with Async Javascript.
Render-blocking Javascript prevents above-the-fold content on your page from being rendered until the javascript has finished loading. This can impact on your page speed and ultimately your ranking within search engines. It can also impact your user’s experience.
Async JavaScript gives you full control of which scripts to add an ‘async’ or ‘defer’ attribute to or to exclude to help increase the performance of your WordPress website.

Async JavaScript

Plugin works as expected, settings are nice and minimal (using core styles) and there aren't any banners, notices or other marketing bloating things up.

Works great!

Async Javascript lets you add 'async' or 'defer' attribute to scripts to exclude to help increase the performance of your WordPress website.

jQuery Image Lazy Load WP vs Async JavaScript