Foursquare co-founder Dennis Crowley drew some attention Wednesday with a check-in at Apple's Cupertino headquarters. The post itself gave no clues but saw him check in at the same time as Holger Luedorf, the company's key organizer for business development and partnerships, as well as its public relations manager Erin Gleason. The latter mentioned she was going to "the next meeting" less than an hour before ending up at Apple.
