SYS-CON MEDIA Authors: Pat Romanski, Gary Arora, Zakia Bouachraoui, Yeshim Deniz, Liz McMillan

Related Topics: Agile Computing, Java IoT, Mobile IoT, Microservices Expo, Microsoft Cloud, @DXWorldExpo

Agile Computing: Article

Engaging the Mobile Visitor

Combining responsive design with performance optimization to deliver exceptional user experiences

In today's hyper-connected world, Web and mobile application performance is playing a more critical role than ever in driving user adoption and engagement. End-users have high expectations - they expect pages to load faster than ever before and they expect richer and more engaging Web experiences and applications.

At the same time, mobile is a fast-growing, global phenomenon that is changing the way we all interact with content, whether for business, information or entertainment. As such, the ability to engage mobile users with fast, quality Web experiences has become a business requirement and a prerequisite for success. Ignore the needs of mobile users, and risk losing a large and growing portion of the business.

Responsive Web Design Adoption Is Growing Fast
Yet, delivering fast, quality experiences in this brave new world isn't exactly easy due to the challenges in optimizing performance across different browsers, screen sizes, networks and devices. Therefore, businesses are looking for techniques that will work equally well on every device. This process is referred to as Responsive Web Design (RWD).

Responsive Web Design[1] is a Web development approach that suggests Web pages should respond to the context in which they're loaded (primarily screen size) and change their user interface accordingly. This technique consists of a mix of flexible grids and layouts, images and an intelligent use of CSS3 media queries. RWD pages contain the HTML required to display all versions of a Web site, including both mobile and desktop views. CSS and JavaScript run in the browser and hide or modify the content to fit the screen size.

The trend of using RWD is growing and growing fast. One of the reasons is that RWD effectively eliminates the need to re-enter the design and development phase each time a new mobile device category comes to market.

As stated, undertaking a RWD strategy sounds like the ideal solution. However, it shouldn't be thought of as a silver bullet for improving the mobile user experience. The reality of successfully engaging mobile users with RWD sites is not always easy. As mobile devices have grown more powerful and networks have become faster and more consistent, the expectations of mobile end-users have also grown.

Delivering Fast and Quality Web Experiences Is Not Easy
If RWD isn't a panacea, what are some of the challenges associated with delivering this type of web site? According to recent research[2] on the composition of RWD sites and the impact on Web performance, 347 RWD[3] sites were tested across different screen resolutions and compared the number of bytes required to download each page across each resolution. The results revealed that 72 percent of RWD sites tested were roughly the same size across different screen resolutions and 22 percent were only slightly smaller.

As important, not only do most pages deliver the same payload across different devices, but also that same payload aligns to the general trend of pages becoming heavier[4] with the average page size close to 1.2 megabytes.

One of the challenges associated with larger, more complex RWD-developed pages is that they need to be delivered to end-users' browsers, which then need to process and render them. On underpowered mobile devices with limited computing power and on constrained wireless and cellular networks this can adversely affect the user experience.

What does delivering large, complex pages on mobile devices mean from an end-user's perspective? Here's a snapshot of the experience of an end-user visiting a US retailer's RWD site's home page on a variety of different best of breed devices/networks. Performance metrics were captured with an empty browser cache using Safari's remote debugging capability. Ten tests for each device/network were run with the median page load time (onLoad event) displayed below. The conclusion is obvious. The delivery of a relatively small 700KB site to a mobile device, over wireless networks, has resulted in serious performance shortcomings.

Figure 1: Example RWD site does not meet end-users' performance expectations

Fundamentally, end users don't care about the underlying technological challenges required to deliver fast, quality experiences to constrained devices over wireless and cellular networks. They just want sites to load fast and work as expected. And end-user expectations just keep getting higher and higher, corresponding to a desire for Web applications that keep getting faster, richer and more engaging.

Steps for Delivering Fast, Quality Responsive Web Design Sites
How do you deliver fast, quality RWD sites? As explained earlier, RWD pages contain the HTML required to display all versions of a website, including both mobile and desktop views. CSS and JavaScript run in the browser and hide or modify the content to fit the screen size. On smartphones, this often means the browser downloads the entire content needed to display the desktop site, only to have CSS/JS hide the vast majority of it.

The first step is to focus on the actual page and the associated objects delivered to the end user. There are also a variety of options available to developers looking to overcome the challenges associated with delivering heavy RWD sites. To start with, move content as close to the end user as possible (i.e., use a Content Delivery Network [CDN]) and leverage optimal delivery mechanisms such as SPDY, an open networking protocol for transporting Web content, that are particularly relevant for wireless networks.

Next focus on the components of the Responsive Web Design application, the HTML, images, JavaScript and CSS objects. To deliver faster pages, focus on:

  • Reducing the number of requests
  • Reducing the number of bytes
  • Accelerating rendering

Let's explore these factors in more details.

Reducing the Number of Requests
The fastest request is the one that isn't made. Each client HTTP request and server response combination represents at least one round-trip on the network. Depending on the end-user's situation and proximity to the origin server, a single round-trip request can take seconds to complete. A single Web page can require dozens of HTTP requests before it can render content, with requests often delaying one another due to the number of connections limited by the specific browser. To reduce round-trips use several techniques to eliminate unnecessary requests such as consolidating multiple CSS and JavaScript files, in-lining small images and leveraging new caching features in HTML5.

Figure 2: A simple optimization to reduce requests is to consolidate multiple CSS or JavaScript files into one

Reducing the Number of Bytes
The math is simple: the larger a web page (measured by bytes), the longer it will take to deliver over a constrained network, and the longer it will take a browser to process and render the content. Images in particular are an issue for RWD sites. Keep file size in check by adjusting image formats, improving cache management, compressing files, and removing data such as comments, whitespaces and image metadata. Automated solutions exist to help deliver the right image resolution to the right device and avoid excessively large images, maintaining image quality at the edge of what the user can perceive, for both small and large screens. For example, a page can be optimized to only load the images that are visible within the current viewport. As the user scrolls down, new images are loaded on demand. Loading images on demand helps improve page load time and also reduces bandwidth for cases where a user doesn't actually scroll down a page. For RWD sites in particular this keeps pages from downloading hidden images, meant for other display sizes or conditions.

Accelerating Rendering
Processing a web page is a complicated process. Browsers employ complex logic during load time, making decisions such as which files to download serially vs. in parallel, which resource types block rendering, and how to manage their connections. At the same time, they need to parse and execute complicated HTML, CSS and JavaScript code, which is often not well defined. Unfortunately, the browser doesn't know sites in advance and is forced to employ generic logic when processing a page. This logic changes between old and new browsers, is limited by backward compatibility and is not customized to a site. Techniques like deferring print style sheets, keeping social buttons from blocking rendering and prefetching the next page are ways to guide the browser into doing the right thing. As a result, users can get a truly fast user experience, attuned to their needs.

Figure 3: The optimized RWD site is significantly faster due to a reduction in bytes, requests and faster rendering

Conclusion
Delivering fast RWD sites is not necessarily easy and requires considerable expertise and resources. Few organizations have developers or expertise in-house to take this on. As RWD evolves new models for delivering fast, quality Web experiences to all users are coming to light. In particular an approach called RESS (Responsive Web Design + Server Side Components)[5] seems to combine the best of current mobile delivery techniques while keeping performance in the forefront. In addition, as mentioned earlier, there are a variety of options available to help developers looking to overcome the challenges associated with delivering heavy RWD sites, such as moving content to a Content Delivery Network (CDN), that has technologies to help accelerate Web performance or leverage optimal delivery mechanisms such as SPDY. The techniques we highlighted here are also helpful, and when followed, can dramatically improve your ability to deliver fast, quality Web experiences while engaging your mobile users.

References

  1. http://alistapart.com/article/responsive-web-design
  2. http://www.guypo.com/uncategorized/real-world-rwd-performance-take-2/
  3. http://mediaqueri.es/
  4. http://www.stevesouders.com/blog/2013/04/05/page-weight-grows-24-year-over-year-not-44/
  5. http://www.lukew.com/ff/entry.asp?1392

More Stories By Lorenz Jakober

Lorenz Jakober is a senior product marketing manager at Akamai Technologies and has extensive experience in the areas of web and mobile application design, performance optimization, usability, and delivery. Prior to joining Akamai Technologies he drove mobile product marketing strategy and the complexity at the edge theme for Compuware Gomez. He is an avid spokesperson and blogger on the topic of mobile and web performance

Comments (1)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Latest Stories
While a hybrid cloud can ease that transition, designing and deploy that hybrid cloud still offers challenges for organizations concerned about lack of available cloud skillsets within their organization. Managed service providers offer a unique opportunity to fill those gaps and get organizations of all sizes on a hybrid cloud that meets their comfort level, while delivering enhanced benefits for cost, efficiency, agility, mobility, and elasticity.
Isomorphic Software is the global leader in high-end, web-based business applications. We develop, market, and support the SmartClient & Smart GWT HTML5/Ajax platform, combining the productivity and performance of traditional desktop software with the simplicity and reach of the open web. With staff in 10 timezones, Isomorphic provides a global network of services related to our technology, with offerings ranging from turnkey application development to SLA-backed enterprise support. Leadin...
DevOps has long focused on reinventing the SDLC (e.g. with CI/CD, ARA, pipeline automation etc.), while reinvention of IT Ops has lagged. However, new approaches like Site Reliability Engineering, Observability, Containerization, Operations Analytics, and ML/AI are driving a resurgence of IT Ops. In this session our expert panel will focus on how these new ideas are [putting the Ops back in DevOps orbringing modern IT Ops to DevOps].
Darktrace is the world's leading AI company for cyber security. Created by mathematicians from the University of Cambridge, Darktrace's Enterprise Immune System is the first non-consumer application of machine learning to work at scale, across all network types, from physical, virtualized, and cloud, through to IoT and industrial control systems. Installed as a self-configuring cyber defense platform, Darktrace continuously learns what is ‘normal' for all devices and users, updating its understa...
Enterprises are striving to become digital businesses for differentiated innovation and customer-centricity. Traditionally, they focused on digitizing processes and paper workflow. To be a disruptor and compete against new players, they need to gain insight into business data and innovate at scale. Cloud and cognitive technologies can help them leverage hidden data in SAP/ERP systems to fuel their businesses to accelerate digital transformation success.
Most organizations are awash today in data and IT systems, yet they're still struggling mightily to use these invaluable assets to meet the rising demand for new digital solutions and customer experiences that drive innovation and growth. What's lacking are potent and effective ways to rapidly combine together on-premises IT and the numerous commercial clouds that the average organization has in place today into effective new business solutions.
Concerns about security, downtime and latency, budgets, and general unfamiliarity with cloud technologies continue to create hesitation for many organizations that truly need to be developing a cloud strategy. Hybrid cloud solutions are helping to elevate those concerns by enabling the combination or orchestration of two or more platforms, including on-premise infrastructure, private clouds and/or third-party, public cloud services. This gives organizations more comfort to begin their digital tr...
Keeping an application running at scale can be a daunting task. When do you need to add more capacity? Larger databases? Additional servers? These questions get harder as the complexity of your application grows. Microservice based architectures and cloud-based dynamic infrastructures are technologies that help you keep your application running with high availability, even during times of extreme scaling. But real cloud success, at scale, requires much more than a basic lift-and-shift migrati...
David Friend is the co-founder and CEO of Wasabi, the hot cloud storage company that delivers fast, low-cost, and reliable cloud storage. Prior to Wasabi, David co-founded Carbonite, one of the world's leading cloud backup companies. A successful tech entrepreneur for more than 30 years, David got his start at ARP Instruments, a manufacturer of synthesizers for rock bands, where he worked with leading musicians of the day like Stevie Wonder, Pete Townsend of The Who, and Led Zeppelin. David has ...
Darktrace is the world's leading AI company for cyber security. Created by mathematicians from the University of Cambridge, Darktrace's Enterprise Immune System is the first non-consumer application of machine learning to work at scale, across all network types, from physical, virtualized, and cloud, through to IoT and industrial control systems. Installed as a self-configuring cyber defense platform, Darktrace continuously learns what is ‘normal' for all devices and users, updating its understa...
Dion Hinchcliffe is an internationally recognized digital expert, bestselling book author, frequent keynote speaker, analyst, futurist, and transformation expert based in Washington, DC. He is currently Chief Strategy Officer at the industry-leading digital strategy and online community solutions firm, 7Summits.
Addteq is a leader in providing business solutions to Enterprise clients. Addteq has been in the business for more than 10 years. Through the use of DevOps automation, Addteq strives on creating innovative solutions to solve business processes. Clients depend on Addteq to modernize the software delivery process by providing Atlassian solutions, create custom add-ons, conduct training, offer hosting, perform DevOps services, and provide overall support services.
Contino is a global technical consultancy that helps highly-regulated enterprises transform faster, modernizing their way of working through DevOps and cloud computing. They focus on building capability and assisting our clients to in-source strategic technology capability so they get to market quickly and build their own innovation engine.
When applications are hosted on servers, they produce immense quantities of logging data. Quality engineers should verify that apps are producing log data that is existent, correct, consumable, and complete. Otherwise, apps in production are not easily monitored, have issues that are difficult to detect, and cannot be corrected quickly. Tom Chavez presents the four steps that quality engineers should include in every test plan for apps that produce log output or other machine data. Learn the ste...
Digital Transformation is much more than a buzzword. The radical shift to digital mechanisms for almost every process is evident across all industries and verticals. This is often especially true in financial services, where the legacy environment is many times unable to keep up with the rapidly shifting demands of the consumer. The constant pressure to provide complete, omnichannel delivery of customer-facing solutions to meet both regulatory and customer demands is putting enormous pressure on...