According to a recent study by comScore, the number of people in the U.S. using multipurpose smartphones such as iPhones, Blackberries, and Droids more than doubled last year. Of those who used mobile devices to access news and information on the Internet, 22.5 million--or 35% of the total--did so on a daily basis.

And this year, that number is expected to skyrocket even further as more companies--T-mobile, AT&T, Spring, Garmin, and even Google--gear up to release their own Android-supported mobile devices. In fact, experts predict that mobile Web usage will overtake PC usage in five years.

The online tools people are using to find and share information with their mobile devices are changing, too. The comScore study shows that the number of people who used smartphones to access a social networking site or blog increased by 427% last year, more than any other category.

So what does this mean for you?

If you want to put your business in front of this exploding online population, then you need to know how they use their mobile devices to access and share information online. You need to know the community sites where they hang out, and understand how they communicate with one another if you want to engage them and build lasting relationships.

Smartphone users are looking for genuine, trustworthy information--recommendations, reviews, rated answers to questions--and they're already geniuses when it comes to filtering out and ignoring inauthentic voices.

Here are five important things you need to do to ensure your business is primed to take advantage of the mobile media storm:

1. Make sure your Web site is mobile-friendly

Mobile users are impatient people. They want information and they want it now. You have to make sure your Web site delivers that information in a way that's useful for them. Fortunately, there are a number of ways to create a quick mobile version of your Web site. If you use WordPress, there are plugins like this one that can help you create a mobile-friendly edition. Or you can use a paid converter such as MoFuse and MOBIFY to do the job.

2. Make sure your Web site is optimized for mobile search

Did you know that both Google and Bing have separate indexes for mobile content? And right now, they return far fewer--and far more localized--results than regular search. So the sooner you get your site optimized to rank well in the search results, the sooner you can put your site in front of the hundreds of millions of mobile device users.

3. Start a Facebook Fan page

Because so many mobile device users are active on Facebook, the world's top social networking site, it only makes sense to have a presence there. Encourage your customers and visitors to sign up as Facebook fans so you can use the networking site to keep in touch with them and share information about your business.

4. Become involved in Twitter

The same logic applies here--Twitter is one of the fastest-growing properties on the Web because it's so easy for people with smartphones to use for accessing and sharing information. If you start building relationships with your visitors and customers via Twitter now, you will be light years ahead of the competition when the smartphone explosion really hits its stride.

5. Make sure you're listed on Google Maps

A huge and growing number of mobile users go to Google Maps first when searching for a local business. You can make sure your site conforms to Google's quality guidelines here.

6. Encourage customers to review your business on Yelp or FourSquare

Yelp is a business review site that has active users in cities all over the world. More than 26 million people a month use Yelp to find information about more than twenty different categories of businesses. FourSquare is somewhat similar in nature. Its members use FourSquare to keep one another informed of their whereabouts. You can also write reviews and recommend places to fellow FourSquare members.

You may think you're not at the right place to start thinking about mobile marketing yet. But no matter where you are in your business building efforts, the time to start laying the foundation for an effective mobile marketing strategy is now. The mobile revolution is happening right now, and if online marketing has taught us anything, it's that the way to be successful is to put your business where the customers are. And that means reaching them on their smartphones.

Allen Moon is Director of Marketing for the Internet Marketing Center. He leads a team of Internet business experts who stay on top of the changing online landscape--testing the latest approaches on real commercial Web sites, then passing on their knowledge in easy-to-use information products, software, and personal training services.

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