J. Crew’s mobile site recently got a makeover. J. Crew Group says it has been working on the new site, which it designed in-house, for more than a year as it sees more shoppers shifting to using their smartphones.

“Statistics estimate a 50% shift of traffic from desktop to mobile across the industry,” J. Crew said announcing the new site.

The site, which is being rolled out over the next several weeks, uses slimmer code for a speedier response time. The mobile site also features a responsive home page, meaning that that the home page for both the desktop and mobile site use the same code but the format of the home page automatically adapts to the screen the consumer is using.

A J. Crew spokeswoman confirms that the percentage of J. Crew’s mobile orders are substantial and growing faster than any other sales channel, but would not give more specifics.

The home page layout for the new mobile site also now showcases editorial content as well as new products. It also features separate entry pages for women’s, men’s, boy’s and girl’s categories that feature stories and products. The site also features larger images.

J. Crew is among the mobile companies ranked in the AppDynamice/Mobile Strategies 360 weekly performance index that measures performance on 30 mobile sites. The J. Crew mobile site has had trouble on and off from week to week struggling at times with sluggish load times, suggesting it could improve its mobile site performance.

For example, in late October, J. Crew fell culprit to a heavy mobile home page weight that resulted in it falling 11 places in the mobile performance rankings for the weekly index compared with a week earlier. That week, J. Crew more than doubled its home page weight on 3G networks going from .7 megabytes to 1.53 megabytes. That led to a longer visually complete time, or the time it takes the browser to finish drawing the visual elements of a page (going from 11.1 to 12.8 seconds). J. Crew did not respond to a request to comment on its mobile site performance.

A fast-responding, streamlined mobile site is a top priority for mobile shoppers. A recent study by e-commerce software provider Episerver finds only 6% of U.S. consumers will wait for a slow-loading mobile site.

The online survey, conducted by research company ResearchNow, polled 1,000 U.S. mobile device owners. Mobile devices included both smartphones and tablets, and 60% of the survey respondents owned both.

More than half (51%) of U.S. consumers ranked slow-loading mobile sites as their biggest frustration when browsing on a mobile device. When experiencing difficulties accessing a mobile site only 6% keep using the site. 42% of consumers leave the site, 26% access the site from their desktop later on, 14% try a competitor, 6% contact customer service, 2% leave negative feedback on social media, 3% have not experienced difficulties and 1% responded “other.” The survey didn’t ask consumers to define a slow or difficult to access mobile site.

The poll also found that 47% of U.S. consumers are less likely to make a purchase from a mobile site if it is difficult to navigate. In the past six months, 35% of U.S. consumers purchased apparel on their smartphones, 31% purchased music, 25% a digital product, such as an app, ebook, music or video, and 24% an entertainment product, such as cinema tickets, concert tickets or restaurant gift cards. Consumers could pick more than one response.