Welcome to the Q&A Forum

Hi Keith, I'd recommend starting by compressing the images (if you haven't already). You mentioned that you've had trouble shrinking the images responsively, but you should be able to use a plugin like WP Smush.it. Compressing images is good for desktop site speed as well. I'd agree with Bradley's CSS recommendation to fix the sizing issue; and for load time you can use CSS image sprites to combine multiple images. I don't necessarily think that there's a problem with checking for the user-agent, and serving a different version of your images, but as Bradley pointed out, they still need to look good on a high res screen. Cloud Four wrote a couple posts that go more in-depth into ways of dealing with responsive images (although these are not specifically Wordpress solutions): http://blog.cloudfour.com/responsive-imgs-part-2/ (from 2011) http://blog.cloudfour.com/8-guidelines-and-1-rule-for-responsive-images/ (from 2013) You might also want to consider consolidating and minifying your CSS and Javascript files if you're concerned about page load time. Here's an article with these and a couple other tips: http://searchengineland.com/how-to-tune-up-responsive-design-websites-to-improve-mobile-seo-124370 Hope that helps!