ryanshoover

Cousett

Easily display a mobile featured image on your posts and page!
Up to 70% of website traffic today is on mobile devices. Sometimes WordPress does not quite resize the featured image in the best way. Avoid this and have full control over your featured images on any device with this plugin.
To add a mobile featured image, simply upload a new image in the meta box right below the WordPress Featured Image called Mobile Featured Image. The new image can be a specifically resized version of your featured image or an entirely new image targeted especially for mobile viewers.
You can add your mobile featured image without worrying about slowing down your site. The mobile image is added to the <code>srcset</code> attribute of your featured image. Vistors’ browsers will automatically download the best image for the size of their screen.
This plugin works by filtering the <code>wp_calculate_image_srcset</code> function and changing the url for all screens under 980w to the mobile featured image. 980w is a reliable breakpoint between the iPhone 6+ and the iPad, two common measures for when a mobile image would be needed.

Mobile Featured Image

WordPress.org

George Stephanis

Helen Hou-Sandi

Andrew Nacin

Kelly Choyce-Dwan

Brandon Lavigne

Chris Coyier

Joe McGill

wilto

Jasper de Groot

tevko

Bringing automatic default responsive images to WordPress.
This plugin works by including all available image sizes for each image upload. Whenever WordPress outputs the image through the media uploader, or whenever a featured image is generated, those sizes will be included in the image tag via the srcset attribute.
Important notes
<ul>
<li>As of WordPress 4.4, images are responsive by default. If you are on WordPress 4.4 or plan to update, you will not need to install this plugin.</li>
</ul>
If you have had this plugin installed since before version 2.5 but are running version 4.4 of WordPress, it is important that you leave the plugin installed. This is because all versions of the plugin before version 2.5 relied on a <code>data-sizes</code> attribute being present on an image in order to provide the responsive markup needed. If the plugin in this case is removed, then images in posts will be left with invalid markup. We are working to address this issue, and you can keep track of our progress here at https://github.com/ResponsiveImagesCG/wp-tevko-responsive-images/issues/178.
You can still use the plugin for advanced image compression support or as a simple way to include the picturefill script. The plugin will fall back to WordPress default functions if responsive image support is detected in your installation.
<ul>
<li>
Version 3.1.0 includes important changes that make this plugin compatible with WordPress version 4.4. Upgrading is highly recommended.
</li>
<li>
As of version 2.5.0, the plugin adds <code>srcset</code> and <code>sizes</code> attributes to images on the front end instead of adding them to the image markup saved in posts.
</li>
</ul>
Full documentation and contributor guidelines can be found on <a href="https://github.com/ResponsiveImagesCG/wp-tevko-responsive-images" rel="nofollow ugc">Github</a>

RICG Responsive Images

Bringing automatic default responsive images to WordPress.

Mobile Featured Image vs RICG Responsive Images