Diamonds may be a girl’s best friend, but there’s a good chance her smartphone is next in line. Diamond retailer JamesAllen.com recently beefed up its mobile site to tie the knot between that love of diamonds and frequent use of smartphones.

James Allen added moving visuals of its diamond and engagement rings on its mobile site a year ago and has enjoyed a dramatic increase in its mobile conversion rate and sales since, says Oded Edelman, CEO and co-founder of JamesAllen.com.

For the past two years JamesAllen.com has had dynamic images on its desktop site, and shoppers asked for the same technology to be available on mobile. That led the retailer to add it to the mobile site as well, Edelman says.

When a shopper visits the mobile site and pulls up an image of a diamond or a ring, the product spins so she can view it from all angles. A consumer can also tap on the image, to stop it from spinning, and turn the image at her own pace.

James Allen developed the image technology for its desktop site in-house. Since the technology uses rapidly moving images, and not a video file, the desktop pages are as heavy as 10 to 15 megabytes, Edelman says. So replicating this technology on the separate mobile site, and getting those heavy pages to load fast, took some work, he says.

“Mobile is an even bigger challenge, since the bandwidth is not as large on the mobile website as it is on desktop,” Edelman says.

After developing and testing the mobile technology for nine months, the retailer brought the image technology onto the mobile site. JamesAllen.com, which has about 300 employees, has about 10 to 12 employees working exclusively on the mobile site, Edelman says.

The pages with the interactive images are half as heavy as the interactive desktop pages and still load in about three seconds when connected to Wi-Fi, or six seconds on 3G or 4G cellular networks, Edelman says.

The retailer achieved this by using 100,000 servers to push the images to the mobile site, he says. The retailer uses content delivery network Akamai Technologies Inc. to do this. Plus, JamesAllen.com reduced the number of images it uses for the 360-degee turns on mobile. On desktop, JamesAllen uses 512 images to create the illusion that a ring is turning. On mobile devices connected to Wi-Fi, James Allen uses 256 images and on mobile devices connected to a cellular network, it uses 128 images, Edelman says.

Since deploying the mobile technology in March 2015, engagement ring purchases made on smartphones increased 466% year over year and the retailer’s mobile conversion rate doubled, Edelman says. Mobile sales are less than a quarter of James Allen’s overall sales, Edleman says.

New York-based James Allen, which previously sold exclusively online, opened its first showroom in New York City last week.