How Mobile-Friendly Is Your Website? If You Don't Know, You're Missing Out on Sales. Mobile isn't an option any more. Your customers are on the move and you'd better be, too.

Years ago, many people still used their desktop or laptop computers to research products and complete online purchases. Those were the days: Businesses could get away with website design that wasn't particularly mobile-friendly.

Those days are long gone.

In today's ever-connected world, shoppers are savvier and more demanding than ever. Business owners have no choice about whether to embrace responsive design in their websites: It is 100 percent necessary. In fact, studies show smartphones have taken over in the online-shopping marketplace.

Whether your website is there to capture leads, inform customers or obtain sales, you must ensure it works seamlessly with all the world's latest smartphones. Not sure if your site measures up? Read on for some tips to make your web presence as responsive as it needs to be in 2016.

Start with a responsive layout.

First, determine whether your site uses a responsive-technology framework. This allows your site's important details to display properly on different devices. Plenty of open-source (free) frameworks exist, so you shouldn't have to look far to find something that suits your needs.

A responsive-technology framework revolves around the layout of elements in a grid. These elements can shift on the grid, depending on the screen size used to access your site. Each component is spaced effectively across different gadgets. The goal is to ensure users enjoy a similar-quality browsing experience no matter how they view your site. It's fine to focus on smartphones and tablets, but don't forget the laptop users and desktop holdouts, either.

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This unified approach to web development also brings search-engine optimization (SEO) benefits. It enables you to avoid a separate URL for mobile devices or stress over different content for various sites that suit specific gadgets.

Helpful resources such as the Mobile Responsive Design Test by StudioPress or Matt Kersley's Responsive Design Testing Tool let you see if your website displays text and graphics correctly across all types of devices and various screen sizes.

Make sure your site works on thumb clicks.

With so many people using their smartphones to check out websites and shop online, your mobile-friendly website must cater to this trend. An avid phone user wants to navigate sites with only his or her "phone hand."

Test whether your site's users can get where they need to go by thumb-clicking the links. Steer clear of "pinches" that require customers to zoom in for content or option buttons. It means your text and graphics are too small and not adequately optimized for smartphone users.

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Build a simple, uncluttered mobile site.

You won't get great results from your website on any platform if the layout isn't clean and unfussy. Keep in mind people stay on a landing page for a few seconds at most to see if a site can meet their needs.

If your site is a big jumble of text and graphics, it's hard for users to scroll through and identify what they need. Frustration will make them click away. On smartphones and other small devices, readability is even more critical. No one wants to squint. And zooming in requires a second hand.

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Too many bells and whistles not only make your site load more slowly but also distract viewers from your key message and information. That delay is a big no-no on its own. Multiple videos, photographs, site seals and virtual reams of copy all will slow down the works.

Use smaller byte-size images and limit the number of graphics on each page. And don't forget to leave plenty of white space throughout your site. These free areas give the reader's eyes a chance to take in other elements and help them recover from processing so much visual information.