You already know the switch to mobile computing is irrevocable and that planning for mobile first is more than just a good idea. What you may not know is that the next generation of social networks could have a dramatic impact on the approach your organization takes to connecting with customers and other stakeholders.

Don’t be embarrassed if you’re not aware of the rise of mobile messaging apps and the real threat they pose to Facebook and other traditional social networks. (And yes, in case you’re wondering, I do find it funny that I’m labeling Facebook a “traditional” network.) They may be a big deal, but here in North America and most of Europe, they haven’t grown big enough to appear on most organizations’ radar screens.

But WhatsApp, one of the most popular of the mobile messaging apps, has more than 300 million active users and processed 27 billion messages in one 24-hour period. By comparison, Twitter—the third-largest social network—has about 200 million active users and handles about 400 million tweets per day. The numbers are equally impressive for WhatsApp’s biggest competitors. Kakao Talk has about 100 million users, Kik reaches about 80 million, and WeChat has over 300 million. Line, Viber and others boast equally impressive user bases.

These apps are starting to invade the U.S. and other regions where they have previously experienced slow growth. WhatsApp already owns 5% of the U.S. market for over-the-top (OTT) apps, those that work over broadband Internet connections and bypass a mobile carrier’s wireless network. Mobile messaging apps have already overtaken SMS text messaging, costing mobile carriers $140 billion in revenue worldwide. Social networks are the next target.

The youth market—notably in Asia, Africa and India—is dropping Facebook and other mainstream tools for mobile messaging apps, motivated by a more discrete network (apps connect with people in your smartphone contact list, a group of people you probably really want to network with, as opposed to the weak ties of most Facebook friends), a highly desirable set of features (including photo and video sharing, games, voice chat, group chat, video calling, and increasingly popular virtual stickers), the ease of access to a tool designed specifically for smartphones, and the ever-growing presence of friends who use the apps.

And, as youth goes, so go other demographic groups. Remember, Facebook was developed initially just for college students.

As I prepared a tech column for IABC’s CW magazine on mobile messaging apps (which won’t appear for several weeks, thanks to production schedules), I dug into the opportunities for brands to connect with their customers. I found only two of apps have made provisions for brands to connect with customers and fans through their networks. Kakao Talk offers Plus Friend, a fee-based service that lets brands and celebrities create their own pages and connect with users. It’s the closest thing to a Facebook or Google+ brand page in the mobile app world. WeChat—from Chinese Internet company TenCent—will let you buy mobile ads to push out to users.

WhatsApp, however, stridently resists any brand presence at all, determined to keep users’ experience spam-free. Others are following suit, at least for now as they’re building up their user bases.

This leads to a serious question marketers and communicators should be pondering now, not later (hence the Pinky and the Brain graphic which, I know, is a stretch): How do we reach our customers and fans if they can’t simply connect with us in order to get our updates, promotions, contests, announcements and images?

Marketing, communications, customer support and other functions have swung pretty far in the social media direction. It’s increasingly common for advertising to direct viewers to Facebook instead of a company URL. If social networkers worldwide do follow the Asia-Africa-India youth to mobile messaging apps, the challenge of establishing those relationships will be considerably harder.

But there is a way.

Among the hundreds of millions of people who will connect with their social graphs via mobile messaging apps are (drum roll, please) your own employees. With no ability to establish a brand-centric presence in the apps, brands should rely on staff to represent them, share news and other content, and serve as ambassadors to the brand.

Smart companies are already enlisting workers through ambassador programs (at companies like Sprint, Dell and PepsiCo), but others continue to be wary of the risk from employees saying too much or the wrong thing. Rather than equip employees to liaise with customers and others, more than 30% of companies still block, restrict or undervalue the use of social networks, according to a recent Microsoft survey.

Unless the popular apps open their networks to brands—or alternative brand-friendly apps kick the current leaders to the curb, which is always a possibility—there aren’t a lot of choices for brands. They can abandon social media altogether, but that genie has long since fled the bottle. They can hope the old guard networks continue to get the job done for them, or they can explore ways employees can fill the gap.

Employees can sent pre-approved messages available via the intranet. They can point people with questions to the right web pages or other resources. They can share coupons. They can express their support for company initiatives. They can alert friends to job openings. They can spread the word about promotions. In other words, marketers’ primary audience becomes employees, who in turn share what they think will resonate with their friends and family.

“Every employee involved” is the mantra of social customer relationship management. Businesses may need to embrace the notion sooner than they’d like if mobile messaging apps continue their startling ascent. Based on the current numbers, I wouldn’t bet against them.