When it comes to mobile websites, it’s not just the design that matters the most—it’s how the elements load.

So says a new Forrester study on responsive web design, which points out the approach’s strengths and weaknesses. (Note: The study is co-sponsored by Moovweb, a company that specializes in responsive delivery techniques.)

The study, “Improving Enterprise Mobility: Meeting Next-Generation Demands for Development, Delivery, and Engagement,” lists factors that come into play when building such sites at an enterprise level, including some that may not be obvious going in. More details:

Front-end design, back-end challenges: Most people think of responsive design as a solution to some of the bother that comes with serving multiple platforms. But it’s largely a front-end approach. According to the survey respondents (executives and other decision-makers in mobile strategy and IT leadership roles spread out over 146 U.S.-based organizations), the back-end stuff is still challenging, with or without responsive design. “When we asked survey respondents how their time is spent on projects across different architecture tiers, the aggregate response was that over 70 percent of their time is spent behind the client—on APIs, middleware, DBMS integration, and infrastructure,” the study states.

Frameworks a poor foundation? Responsive web frameworks such as Zurb Foundation and the Twitter-created Bootstrap platform have drawn attention for their ability to simplify the design tasks that come with responsive design (such as setting “breakpoints,” or web browser widths at which the design scales back). Many survey participants said the frameworks made things easier to a point—but when developers reached limitations imposed by the platforms, their use hurt the scope of development. “Frameworks typically tend to operate around configuration or convention; they are designed to do certain things very well (e.g., automate setting breakpoints), but become restrictive once you move outside their design sweet spot,” the study says. While more than 85 percent of those whose organizations built responsive sites said they came in at or below budget for the site, 37 percent reported having to scale back scope to get the project done on time.

Deliver responsively: The study’s main point? In some cases, it could make more sense to take the elements of the site and deliver them based specifically on the platform, something the study calls “responsive delivery.” The setup relies on existing content on a desktop site that is retrofitted down based on the size of the screen. The approach could prove beneficial, as it would require data-conscious mobile users to download less code each time they load the site, and would allow better utilization of back-end techniques like server caching to give users the best possible experience. On top of this, such sites would be able to utilize mobile-only technology like geolocation to build their content.

The full study is available at the Moovweb website [PDF].

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