Social networking is one of the fastest-growing activities among mobile users domestically and worldwide, so marketers must follow the eyeballs and develop a mobile social strategy, according to eMarketer.

As one of the primary ways mobile users communicate with one another, social networking?the exchange and discussion of information, content and media on shared communities such as Facebook, MocoSpace and foursquare?is proving a significant driver of Internet usage on mobile devices. In the United States, mobile social networkers will total 56.2 million by 2013, accounting for 45 percent of the mobile Internet user population, eMarketer predicts.

?The main takeaway is the growth and usage of social networks on mobile devices as a means of communication, especially for younger mobile users, say, 13-34,? said Noah Elkin, senior analyst at eMarketer, New York.

?For that reason, it?s a space that bears close, marketers should keep a close eye on as it evolves?and it is evolving quickly?to see how they can participate in these conversations that are taking place among consumers,? he said.

?One of important conclusions of the report is that the value marketers can provide comes from offering consumers a combination of utility, relevance and fun?that?s where they?ll ultimately find the pay-off.?

The study by eMarketer predicts 1.4 billion mobile Internet users out of a total of 5.6 billion mobile subscribers worldwide in 2013, up from 505 million mobile Internet users out of 4.6 billion mobile subscribers worldwide in 2009.

In addition, eMarketer predicts that the number of mobile users accessing social networks from their mobile devices will reach 607.5 million worldwide by 2013, representing 43 percent of global mobile Internet users.

Yet, as impressive as these numbers are, gaining a voice in the conversations taking place across mobile social networks will prove challenging for marketers. Both mobile and social still constitute emerging channels in the eyes of brands and agencies.

As such, most marketers are in the process of sorting out key issues, notably internal ownership and scalability of mobile-social programs. Budgeting and definitions of ROI likewise continue to evolve, according to eMarketer. In addition, dedicated mobile-social ad inventory remains limited.

Place has power
The biggest near-term opportunities will come from location-aware applications, services and offers, which provide value in the form of contextual relevance and which are increasingly popular among smartphone owners.

Social networking has proven to be a big hit with mobile users, but for now the main beneficiaries of all their mobile Internet activity may be the mobile carriers.

Increased activity may put a near-term burden on mobile networks, but it will ultimately boost adoption of the mobile Internet, especially as mobile users increasingly regard social-network access as a must-have.

However, as with many aspects of mobile, marketing activity and ad revenues have lagged far behind actual usage.

But make no mistake marketers, the mobile social networking space merits close observation. The lack of advertising success on mobile social networks to date is not a reason for marketers to ignore them.

To the contrary, the mobile social networking space is evolving so quickly that it should be watched closely for new and enhanced opportunities to participate, including in location-based social networks, according to eMarketer.

Marketers need to rethink their value equation. Mobile is the most personal communication platform, and social networking is a highly personal activity, even if much of users? activity takes place in the public eye.

For marketers, treading lightly is recommended. Ultimately, marketers interested in adding value will need to provide consumers with a measure?and measurable degree?of utility, relevance and fun.

The challenge?and payoff?for marketers will come from finding effective ways to tap into mobile social network users? locations and connecting places with people and things, according to eMarketer.

?Location-aware targeting within apps is interesting and evolving?there?s been a lot of emphasis on networks like foursquare and Loopt, and while MocoSpace and BrightKite have been around for a number of years, foursquare changed the equation by adding a social competition element,? Mr. Elkin said.

?Foursquare is still embryonic, but it may have hit on something that will have some staying power?combining social networking and gaming with location, finding friends, checking in places,? he said. ?Can they develop a business model where marketers can present offers that are contextually relevant?

?We see some of that on foursquare but it?s pretty ad hoc, and there are scalability questions, because it works well in densely populated cities, but less well in more rural areas, which is the same for all location-based social networks.?

For now, the challenge of working out the best way for brands and agencies to tap into mobile social networks remains.

?Separately mobile and social are on brands? radar, but both are in the emerging category individually, and when you combine the two, you have an ownership issue,? Mr. Elkin said. ?Who?s in charge of a program that crosses over between mobile and social?

?It?s an ongoing issue being worked out on the brand side at the moment as both mobile and social are becoming viewed as essential elements of their overall marketing strategy,? he said. ?It?s important to look at it in a holistic way, mobile as a channel for reaching users, social as a channel for reaching users, and mobile social networking as a way a brand?s audience or target market communicates with each other.

?Marketers need to keep an eye on the space and figure out ways to reach these users, if not advertising in traditional way, figure out applications that tap into this particular behavior.?