“Content matters!” “Comp with real copy!” “Have a plan!” By now, you’ve probably heard the refrain: making mobile work is hard if you don’t consider your content. But content knowledge isn’t just about ditching lorem ipsum in a couple of comps.
Countless organizations now have a decade or two’s worth of Web content — content that’s shoved somewhere underneath their redesigned-nine-times home page. Content that’s stuck in the crannies of some sub-sub-subnavigation. Content that’s clogging up a CMS with WYSIWYG-generated markup.
Messy, right? Well, not as messy as it will be — because legacy content is the thing that loves to rear its ugly head late in the game, “breaking” your design and becoming the bane of your existence.
But when you take the time to understand the content that already exists, not only will you be able to ensure that it’s supported in the new design, but you’ll actually make the entire design stronger because you’ll have realistic scenarios to design with and for — not to mention an opportunity to clean out the bad outdated muck before it obscures your sparkly new design.
When you’re working on something new and fun, ignoring the deep recesses of content is tempting. After all, you’ve got a lot to think about already: designing for touch, dealing with ever-changing screen sizes, adding geolocation features, maybe even blinging things out with a few badges.
But if content parity matters to you (and it damn well should if you care one whit about the “large and growing minority of Internet users” who always or mostly access the Web on a mobile device), then at some point you’ll have to deal with the unruly content lurking underneath your website’s neat surface.
Why? Because chances are there’ll be stuff out there that you’ve never thought about, much less designed for. And all that stuff has to go somewhere — too often, shoehorned into a layout it was never meant to inhabit, or perhaps not even migrated into a new template but instead left to wither in an outdated, mobile-unfriendly design.
Take navigation. As Brad Frost has written, designing small-screen navigation for small websites is simply tricky, any way you slice it.
Hard as it already is, it becomes downright impossible if you haven’t dealt with your legacy assets first. You’re sure to end up with problems, like a navigation system that only works for two levels of content when you actually have four levels to contend with, making all of that deeper information accessible only with hard to manage (and find) text links — or, worse, making it completely inaccessible except through search.

Mark Boulton has written eloquently on content-out design — the concept of determining how your design should shift for varying displays by focusing not on screen sizes, but on where your content naturally breaks down. It’s excellent advice.
But if you’re trying to work with a website with thousands of URLs — or anything more than a few dozen, really — you have to ask: Which content do I design with? Unless you’re relying on infinite monkeys designing infinite layouts to create custom solutions for every single page, you’re going to have to rely on representative content: a set of content that demonstrates the variety of information that the experience needs to support.