In the 1970s, Coca-Cola wanted to teach the world how to sing (in perfect harmony). Today, Foursquare wants to teach the world how to check-in with your smartphone at your favorite shops and restaurants.

Checking-in may seem like something only for young people with too much time on their hands. But consider these numbers: 30 million users, 5 million check-ins a day, 3 billion total check-ins since Foursquare was launched 3 years ago. Sounds pretty mainstream to me.

The app is appealing partly because it’s also a game: the person who checks in the most at a certain location is declared Mayor. In our irony-heavy age, being mayor is obviously a fake title, though it can result in real perks like free drinks and other discounts awarded to loyal customers. And on the flip side, many companies are using Foursquare, including, ironically, Coca-Cola, to lure customers and boost revenue.

So who is the most active Foursquare user in the the world? That’s unclear (though see this interesting heat map of Foursquare check-ins worldwide). But the most active Foursquare user in technology-mad Silicon Valley, according to Wired.com, appears to be Apple co-founder, Steve Wozniak. He is the mayor of 24 places in the Valley alone, most of them retailers in the southern suburbs of the Valley near his Los Gatos home.

“This is a man building a Foursquare empire,” according to Wired. “With 4,183 check-ins, Mayor Woz shows no signs of slowing down and could become the mayor of every building, landmark and prison in the Silicon Valley — probably while riding his Segway.”

Credit: TheDigitalStory.com

Kinda like this.

You can check out Woz and his impressive, near-obsessive check-in habit via his Twitter account @SteveWoz. Indeed, by the time you read this, Woz should have checked into the Grand Hyatt Hotel in Manhattan, where he will be the featured speaker at the Avaya Evolutions New York conference on Tuesday, April 8th.

Evolutions is Avaya’s traveling North and South American roadshow, where we bring our technology, products and experts to you the user, rather than force you to fly hours to Orlando or Vegas. Woz will reminisce about Apple and share his thoughts about the future of technology at the afternoon keynote, as he did at the Avaya Evolutions Bay Area last fall.

About 2,000 people are registered to attend Avaya Evolutions New York. If you can’t check-in and attend, you can follow the news and see the pictures via my blog or on Twitter @EricYLai, or also via the @Avaya Twitter account.

Read more: The Benefits of Using Foursquare