Per­haps the largest and busiest start­up in the whole of New York is Foursquare. Found­ed three years ago back in 2009 by Naveen Sel­vadu­rai and Den­nis Crow­ley, the loca­tion check-in mobile app has so far earned around $70 mil­lion, in part thanks to smart mobile adver­tis­ing, and is now focus­ing on rev­enue for the first time.

The com­pa­ny has nev­er been over­ly focused on rev­enue rais­ing before, but just recent­ly hired its first ever Vice Pres­i­dent of Sales in the form of Rob Wilk and a Chief Rev­enue Offi­cer in for­mer iAds head Steven Rosen­blatt. At the moment Rosen­blatt has ten peo­ple work­ing with him in sales strat­e­gy, account man­age­ment and sales sup­port, and he is still in the process of hir­ing more.

“We’ve received tons of inbound from agen­cies, we just didn’t have the band­width or the team to han­dle it before,” Rosen­blatt told Busi­ness Insid­er. While busi­ness devel­op­ment has been run by Hol­ger Lue­dorf for a num­ber of years now, this will be the very first time that the start­up has instat­ed a sales team. Rosen­blatt notes that they wait­ed until the com­pa­ny had enough user data before they began to focus on revenue.

With 2.5 bil­lion check-ins, five mil­lion of which hap­pen every day, and a total of 20 mil­lion users, Foursquare is unde­ni­ably one of the largest mobile-first firms. Their new office is sit­u­at­ed on the tenth floor of 568 Broad­way, a res­i­dence its 135 employ­ees also share with the likes of Thril­list, Zoc­Doc and Equinox. The team moved in back in Feb­ru­ary but now they are ful­ly up and run­ning and com­plete­ly fur­nished, with each and every room dec­o­rat­ed in the man­ner of a check-in. There is a Her­bi­vore room which is decked out with earthy mate­ri­als includ­ing but not lim­it­ed to plants, gym­nas­tic rings, tons of games, pic­nic tables, a mini amp­ithe­ater, loads of food, a Swarm room which looks rather like a bee hive, and even a week­ly keg. Any­one who thinks that sounds like a fun place to work might just be in luck as well, giv­en that the com­pa­ny is in the midst of hir­ing on both coasts.