Retina.js is an open source script that makes it easy to serve high-resolution images to devices with retina displays.
http://retinajs.com/
JavaScript Libraries and Functions · Media
Get access to data on 1,960,020 websites that are Retina JS Customers. We know of 562,527 live websites using Retina JS and an additional 1,397,493 sites that used Retina JS historically and 271,107 websites in the United States.
Get a list of 1,960,020 websites using Retina JS which includes location information, hosting data, contact details, 562,527 currently live websites and an additional 244,619 domains that redirect to sites in this list. 1,397,493 sites that used this technology previously and 271,107 websites in the United States currently using Retina JS.