Here's What Foursquare HQ Looked Like Right Before The Biggest Launch In Company History (PHOTO TOUR)

Photo: Dan Frommer, Business Insider

Foursquare is in the middle of the biggest launch blitz in its 2-year history: A huge new update of its iPhone and Android apps, a big new platform for merchants that could eventually become its money-maker, and a partnership with American Express, its most impressive yet.South by Southwest — Foursquare’s Super Bowl — starts this week, and most of the company’s 50-plus employees are going.

That means super-long hours, extra doses of caffeine, and a serious buzz of productivity at its New York headquarters.

We visited Foursquare HQ yesterday evening, just a few hours before the company flipped the switch on its new iPhone app. And, of course, we brought our camera.

Getting off the elevator, you can tell that people have been working well into the night recently. Pictured: Server engineers Nate Folkert, Kushal Dave, Justin Moore, Matthew Rathbone, Neil Sanchala, and Jon Hoffman.

It's not loud -- lots of headphones and typing -- but people are not goofing around, either. There is a buzz of productivity. Pictured: Tim Julien, Kushal Dave, David Blackman, Siobhan Quinn, and Dolapo Falola.

There is even a good-luck Justin Bieber poster up on display.

Hey, it's Foursquare cofounder and CEO Dennis Crowley, clutching a coffee. We're guessing it's no. 3 or 4 for the day.

Crowley chats across the room with product manager Noah Weiss, who recently joined the company from Google

Over in a corner, it's product manager Siobhan Quinn, cofounder Naveen Selvadurai, and recruiter Susan Loh.

Naveen, we hope, is trying out a secret new Foursquare iPad app. (No, we don't know.)

Siobhan was Foursquare's only product manager for a long time. She, too, joined from Google, where she was a PM for Blogger.

You'd bring slippers to the office, too, if you were going to be here past midnight.

Server engineer Jon Shea has taken over a quiet, comfy corner of the office.

Biz dev director Eric Friedman used to work for Union Square Ventures, one of Foursquare's investors, and has a marketing background.

Even the bathrooms have little badges.

Obligatory kitchen photo. Healthy snacks!

A look outside at the East Village, including the building where AOL is based.

Biz dev associates Dev Anand and Zach Bouzan-Kaloustian.

Server engineers Dolapo Falola and Jorge Ortiz are trying to contain how much fun they're having.

Engineers Tim Julien and Jason Lizska with a printout of Naveen's head. Jason worked on Foursquare's revamped merchant platform.

Can you feel the mental energy?!

Nate Folkert on the server team wonders how someone checked in from THERE.

Legendary engineering lead Harry Heymann, former Google/Dodgeball employee and early Foursquare employee, wasn't around. But we found this on his desk. Interesting! (Dodgeball was Crowley's first attempt at a location startup, before that was cool. Google bought it and eventually shut it down, after Crowley left.)

That's mobile client engineer lead Tim Vetter in the plaid shirt. He used to work with Dennis at Vindigo. Next to him is engineer intern David Villareal.

Basically the only art in the office right now is this painting of Internet legend Clay Shirky.

Here's Foursquare's lead designer, Mari Sheibley, who designs the badges. Designer Matt Healy is in the background; he worked on the cool Foursquare 2010 infographic.

You, too, can contribute to the Feature Wishlist.

BUSTED: Dennis catches us peeking at the secret whiteboards!

Crowley in the zone at his desk.

Here's a drawing of Harry Heymann. Nice!

Crowley's old Google business card, from the Dodgeball days. (Inspiration to keep cranking!)

Dennis has picked up some gadgets for testing, like the PlayStation phone.

Nina Yiamsamatha (Community Support Coordinator) and Jeff Hu (BlackBerry engineer). Nina won people over with a resume designed like a Foursquare check-in history page.

Hey, it's the Naveen and Dennis Gap ad in a conference room. What else is in there?

It's product head Alex Rainert! He's been on the phone with reporters all day, talking up the new Foursquare 3.0 app. Rainert joined the company last year; he was previously the cofounder of Dodgeball with Dennis Crowley.

Dodads, including Foursquare's Crunchie award.

Our gracious tour guide, Foursquare PR rep Erin Gleason, another former Googler.

Jonathan Crowley works on media partnerships, and is Dennis Crowley's brother. Here, he's mopping up a coffee that we may or may not have played an indirect role in spilling. (Sorry!)

Hey, nice water bottle! OK, we've probably worn out our welcome.

On the way out, we take a peek at t-shirt/swag zone.

Badge pins!

The bike corner, and a cardboard cutout of Naveen.

Cool way to check-in to Foursquare: Tap your NFC (near field communication) equipped Android phone to that blue badge, and you'll be automatically checked in to Foursquare HQ.

Crowley tweets that he was at the office past 3 a.m. and Skyped into a meeting with Amex at 8:30. Crazy times!

Now check out how far Foursquare has come since the last time we visited for a photo tour...

Tour the Foursquare, Curbed, and Hard Candy Shell offices, circa 2009 →

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