[2] In May 2010 Rentzsch announced[3] that he would no longer operate the conference due to a dissatisfaction with Apple's policies toward iPhone OS development and the lack of a strong negative reaction from the Apple developer community.
[2] Due to that year's Chicago Marathon, attendees unable to stay downtown were provided free passes to the Chicago 'L' railway system for the weekend (an arrangement referred to as "Plan 'L'").
[6] The second C4 conference was held at the Chicago City Centre Hotel on August 10–August 12, 2007.
[9] Daniel Lyons, senior editor at Forbes magazine and writer of The Secret Diary of Steve Jobs under the pseudonym "Fake Steve Jobs", was scheduled to speak at C4 but was unable due to an illness.
In these talks, speakers were held to 5 minutes per presentation, with each slide having a maximum of 20 seconds on screen.