Thanks for the reply,
Just to clarify, the plugin auto resizes the full res retina image that is uploaded by creating a half size version, or does the user need to upload two versions. In my example, if want a retina 1200×1200, I would upload that and designate that as the retina version and the plugin does what exactly?
Also, again to clarify, I realize that with 4.4, WP delivers a resized image dependent on the screen size. Without the plugin, can you tell WP to use a full size for retina and a half size for desktop?
Sorry for so many questions, just trying to differentiate what the plugin does compared to the new version of WP.